ci: bump actions/cache from 3 to 4 (#422)

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -34,7 +34,7 @@ jobs:
         id: composer-cache
         run: echo "dir=$(composer config cache-files-dir)" >> $GITHUB_OUTPUT
 
-      - uses: actions/cache@v3
+      - uses: actions/cache@v4
         with:
           path: ${{ steps.composer-cache.outputs.dir }}
           key: ${{ runner.os }}-composer-${{ hashFiles('**/composer.lock') }}