Use Go 1.21 for Go tracing checks

Author: mbg

.github/workflows/__go-tracing-autobuilder.yml

@@ -4,6 +4,9 @@ operatingSystems: ["ubuntu", "macos"]
 env:
   DOTNET_GENERATE_ASPNET_CERTIFICATE: "false"
 steps:
+  - uses: actions/setup-go@v4
+    with:
+      go-version: "1.21.1"
   - uses: ./../action/init
     with:
       languages: go

.github/workflows/__go-tracing-custom-build-steps.yml

@@ -2,6 +2,9 @@ name: "Go: tracing with custom build steps"
 description: "Checks that Go tracing traces the build when using custom build steps"
 operatingSystems: ["ubuntu", "macos"]
 steps:
+  - uses: actions/setup-go@v4
+    with:
+      go-version: "1.21.1"
   - uses: ./../action/init
     with:
       languages: go

.github/workflows/__go-tracing-legacy-workflow.yml

@@ -4,6 +4,9 @@ operatingSystems: ["ubuntu", "macos"]
 env:
   DOTNET_GENERATE_ASPNET_CERTIFICATE: "false"
 steps:
+  - uses: actions/setup-go@v4
+    with:
+      go-version: "1.21.1"
   - uses: ./../action/init
     with:
       languages: go