Add optional Windows and Ubuntu lowest tests to CI

Updated the CI workflow to include optional tests on Windows and the Ubuntu lowest environment. Also upgraded actions/checkout and actions/cache versions to v4.

.github/workflows/continuous-integration.yml

@@ -18,6 +18,16 @@ on:
         required: false
         type: string
         default: '8.4'
+      windows:
+        description: Run tests on Windows
+        required: false
+        type: boolean
+        default: false
+      ubuntu_lowest:
+        description: Run tests on ubuntu-lowest environment
+        required: false
+        type: boolean
+        default: false
       script:
         description: Additional scripts to run
         required: false
@@ -30,35 +40,37 @@ env:
 jobs:
   phpunit:
     name: PHPUnit
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
     strategy:
+      fail-fast: false
       matrix:
+        php-version: ${{ fromJson(inputs.old_stable) }}
+        dependencies: [highest, lowest]
+        os: [ubuntu-latest]
         include:
-          # Old stable versions
-          - php-version: ${{ fromJson(inputs.old_stable) }}
-            os: ubuntu-latest
-            dependencies: highest
-          - php-version: ${{ fromJson(inputs.old_stable) }}
-            os: ubuntu-latest
-            dependencies: lowest
-
           # Current stable version
           - php-version: ${{ inputs.current_stable }}
-            os: windows-latest
+            os: ubuntu-latest
             dependencies: highest
             experimental: false
-          - php-version: ${{ inputs.current_stable }}
-            os: ubuntu-latest
+
+          # Windows test (optional)
+          - if: ${{ inputs.windows }}
+            php-version: ${{ inputs.current_stable }}
+            os: windows-latest
             dependencies: highest
             experimental: false
-          - php-version: ${{ inputs.current_stable }}
+
+          # Ubuntu lowest test (optional)
+          - if: ${{ inputs.ubuntu_lowest }}
+            php-version: ${{ inputs.current_stable }}
             os: ubuntu-lowest
-            dependencies: lowest
+            dependencies: highest
             experimental: false
 
     steps:
       - name: Checkout
-        uses: actions/checkout@v3
+        uses: actions/checkout@v4
         with:
           fetch-depth: 0
 
@@ -71,6 +83,7 @@ jobs:
 
       - name: Get composer cache directory
         id: composer-cache
+        shell: bash
         run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
 
       - name: Cache dependencies