GH Actions: update for the upcoming release of PHP 8.6

.github/workflows/test.yml

@@ -34,10 +34,11 @@ jobs:
           - '8.3'
           - '8.4'
           - '8.5'
+          - '8.6'
         experimental: [false]
 
         include:
-          - php: '8.6'
+          - php: '8.7'
             experimental: true
 
     name: "Test on PHP ${{ matrix.php }}"
@@ -66,21 +67,14 @@ jobs:
 
       # Install dependencies and handle caching in one go.
       # @link https://github.com/marketplace/actions/install-php-dependencies-with-composer
-      - name: Install Composer dependencies - normal
-        if: ${{ matrix.experimental == false }}
+      - name: Install Composer dependencies
         uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
         with:
+          # For PHP "nightly", we need to install with ignore platform reqs as not all dependencies allow it.
+          composer-options: ${{ matrix.experimental == true && '--ignore-platform-req=php+' || '' }}
           # Bust the cache at least once a month - output format: YYYY-MM.
           custom-cache-suffix: $(date -u "+%Y-%m")
 
-      # For the PHP "nightly", we need to install with ignore platform reqs as not all dependencies allow it.
-      - name: Install Composer dependencies - with ignore platform
-        if: ${{ matrix.experimental == true }}
-        uses: "ramsey/composer-install@65e4f84970763564f46a70b8a54b90d033b3bdda" # 4.0.0
-        with:
-          composer-options: --ignore-platform-reqs
-          custom-cache-suffix: $(date -u "+%Y-%m")
-
       - name: Lint
         run: composer phplint -- --checkstyle | cs2pr