Cleanup CI matrix

Author: johnnyshields

.github/workflows/test.yml

@@ -8,23 +8,15 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        os: [ubuntu-20.04] # macos-latest
-        ruby-version: [3.0, 3.1, 3.2, jruby-9.3, jruby-9.4, truffleruby]
-        include:
-          - os: macos-latest
-            ruby-version: 3.0
-          - os: macos-latest
-            ruby-version: 3.1
-          - os: macos-latest
-            ruby-version: 3.2
-          - os: macos-latest
-            ruby-version: jruby-9.3
-          # 2023/03/07 - JRuby 9.4 on MacOS is skipped for now.
-          # Seems to be a JRuby-side issue.
-          # - os: macos-latest
-          #   ruby-version: jruby-9.4
-          - os: macos-latest
-            ruby-version: truffleruby
+        os:
+          - ubuntu-20.04
+          - macos-latest
+        ruby-version:
+          - 3.0
+          - 3.1
+          - 3.2
+          - jruby-9.4
+          - truffleruby
     runs-on: ${{ matrix.os }}
     steps:
       - uses: actions/checkout@v2