Update ci.yml

We cannot run a git diff, because usort may sort equal rules differently on different PHP versions.

.github/workflows/ci.yml

@@ -48,7 +48,7 @@ jobs:
 
     steps:
     - name: Checkout
-      uses: actions/checkout@v3
+      uses: actions/checkout@v2
 
     - name: Override PHP ini values for JIT compiler
       if: matrix.compiler == 'jit'
@@ -62,15 +62,6 @@ jobs:
         extensions: ${{ env.PHP_EXTENSIONS }}
         ini-values: ${{ env.PHP_INI_VALUES }}
 
-    - name: Cache Composer packages
-      id: composer-cache
-      uses: actions/cache@v3
-      with:
-        path: vendor
-        key: v5r2-${{ runner.os }}-php-${{ matrix.php-version }}-${{ hashFiles('**/composer.lock') }}
-        restore-keys: |
-          v5r1-${{ runner.os }}-php-${{ matrix.php-version }}-
-
     - name: Install dependencies
       uses: php-actions/composer@v6