CI: fix Julia 1.10 lts dev step (registry refresh + active project skip)

Two distinct bugs that together cause every `(<group>, lts)` SublibraryCI
or CI.yml job to fail at the develop step before tests even start:

## 1. Develop step runs before registry refresh

`CI.yml` performs a `Pkg.develop(specs)` of every local `[sources]` entry
in the top-level `Project.toml`. That develop's resolver checks every
transitively required *registered* dep against the depot's General
registry copy. The pkg-server's General copy is often 24-72h stale and
does not yet include current SciMLBase v3 / CoverageTools / etc., so the
resolve aborts with `expected package <X> to be registered` and the job
is red before any test runs. Examples:

- `test (Integrators_I, lts)` — `expected package SciMLBase [0bca4576] to be registered`
- `test (InterfaceIII, lts)` — `expected package CoverageTools [c36e975a] to be registered`

`CI.yml` already had a "Refresh General registry directly from git" step
that reclones the registry, but it was running *after* the develop step,
so develop hit the stale copy. Reorder so registry refresh runs first.

`SublibraryCI.yml` had no registry refresh step at all and hit the same
class of failure on lts. Add the same registry refresh step before its
develop step.

The Julia 1.11+ matrix cells are unaffected: `[sources]` is supported
natively there and the develop step is a no-op (the script's `VERSION <
v"1.11.0-DEV.0"` guard).

## 2. Transitive [sources] walk in test/runtests.jl tries to develop the active project

`test/runtests.jl`, when it activates a sublibrary (`Pkg.activate(joinpath(lib_dir, base_group))`),
walks `[sources]` recursively to develop every transitive local path
dep — needed because nested sublibraries reference each other. Several
sublibrary `Project.toml`s have `[sources]` cycles back to the active
sublibrary (e.g. `lib/DiffEqDevTools/Project.toml` lists
`OrdinaryDiffEqCore = {path = "../OrdinaryDiffEqCore"}`). When testing
`lib/OrdinaryDiffEqCore`, the walk reaches DiffEqDevTools and queues
`../OrdinaryDiffEqCore` for develop, which Pkg refuses with:

    package `OrdinaryDiffEqCore [bbf590c4]` has the same name or UUID as
    the active project

Pre-seed the `developed` set with the active project's path so the walk
skips it.

These are pre-existing master CI infrastructure bugs, unrelated to any
specific in-flight PR.

Co-Authored-By: Chris Rackauckas <accounts@chrisrackauckas.com>

Author: ChrisRackauckas

.github/workflows/CI.yml

@@ -98,6 +98,21 @@ jobs:
           key: julia-cache;workflow=${{ github.workflow }};job=${{ github.job }};os=${{ runner.os }};group=${{ matrix.group }};version=${{ matrix.version }};run_id=${{ github.run_id }};run_attempt=${{ github.run_attempt }}
           restore-keys: |
             julia-cache;workflow=${{ github.workflow }};job=${{ github.job }};os=${{ runner.os }};group=${{ matrix.group }};version=${{ matrix.version }};
+      - name: Refresh General registry directly from git
+        shell: julia --color=yes --project=. {0}
+        run: |
+          using Pkg
+          # Force a fresh git clone of General to dodge pkg server lag.
+          # Must run BEFORE the Pkg.develop step below: that step's resolve
+          # needs current versions of registered deps (e.g. SciMLBase v3,
+          # CoverageTools), and the cached pkg-server registry is often
+          # several days stale, so develop's resolve fails with "expected
+          # package <X> to be registered".
+          try
+              Pkg.Registry.rm("General")
+          catch
+          end
+          Pkg.Registry.add(Pkg.RegistrySpec(url = "https://github.com/JuliaRegistries/General.git"))
       - name: Develop local path deps (Julia < 1.11)
         shell: julia --color=yes --project=. {0}
         run: |
@@ -119,16 +134,6 @@ jobs:
               isempty(specs) || Pkg.develop(specs)
             end
           end
-      - name: Refresh General registry directly from git
-        shell: julia --color=yes --project=. {0}
-        run: |
-          using Pkg
-          # Force a fresh git clone of General to dodge pkg server lag.
-          try
-              Pkg.Registry.rm("General")
-          catch
-          end
-          Pkg.Registry.add(Pkg.RegistrySpec(url = "https://github.com/JuliaRegistries/General.git"))
       - uses: julia-actions/julia-buildpkg@v1
       - uses: julia-actions/julia-runtest@v1
         with:

.github/workflows/SublibraryCI.yml

@@ -82,6 +82,21 @@ jobs:
         continue-on-error: true
         with:
           cache-compiled: 'false'
+      - name: Refresh General registry directly from git
+        shell: julia --color=yes --project=. {0}
+        run: |
+          using Pkg
+          # Force a fresh git clone of General to dodge pkg server lag.
+          # Must run BEFORE the Pkg.develop step below: that step's resolve
+          # needs current versions of registered deps (e.g. SciMLBase v3),
+          # and the cached pkg-server registry is often several days stale,
+          # so develop's resolve fails with "expected package <X> to be
+          # registered".
+          try
+              Pkg.Registry.rm("General")
+          catch
+          end
+          Pkg.Registry.add(Pkg.RegistrySpec(url = "https://github.com/JuliaRegistries/General.git"))
       - name: Develop local path deps (Julia < 1.11)
         shell: julia --color=yes --project=. {0}
         run: |

test/runtests.jl

@@ -61,6 +61,13 @@ end
         # a higher-level sublibrary like OrdinaryDiffEqDefault.
         if VERSION < v"1.11.0-DEV.0"
             developed = Set{String}()
+            # Never develop the active project: when sublibraries cyclically
+            # reference each other via [sources] (e.g. DiffEqDevTools points
+            # back at OrdinaryDiffEqCore), the transitive walk below would
+            # otherwise try to `Pkg.develop` the active project itself, which
+            # Pkg refuses with "package <X> has the same name or UUID as the
+            # active project".
+            push!(developed, normpath(joinpath(lib_dir, base_group)))
             specs = Pkg.PackageSpec[]
             queue = [joinpath(lib_dir, base_group)]
             while !isempty(queue)