Update GitHub Action actions/cache from v2 to v3

Author: lyrixx

.github/workflows/ci.yml

@@ -49,7 +49,7 @@ jobs:
               run: echo "::set-output name=dir::$(composer config cache-files-dir)"
 
             - name: Cache composer dependencies
-              uses: actions/cache@v2
+              uses: actions/cache@v3
               with:
                   path: ${{ steps.composer-cache.outputs.dir }}
                   key: ${{ runner.os }}-composer-${{ github.sha }}