CI: Use common cache restore and cache save action on GitHub Actions

Unfortunately a composite action cannot have a `post:` step like
JavaScript actions are allowed to have, so we need to explicitly call
the post/save actions ourselves from the workflow file when we want to
save Toolchain/QEMU/ccache caches.

Co-Authored-By: Timothy Flynn <trflynn89@pm.me>

.github/workflows/libjs-test262.yml

@@ -70,23 +70,12 @@ jobs:
       - name: Check versions
         run: set +e; g++ --version; g++-13 --version; python --version; python3 --version; ninja --version
 
-      - name: TimeZoneData cache
-        uses: actions/cache@v4
+      - name: Restore Caches
+        uses: ./.github/actions/cache-restore
         with:
-          path: ${{ github.workspace }}/libjs-test262/Build/caches/TZDB
-          key: TimeZoneData-${{ hashFiles('Meta/CMake/time_zone_data.cmake') }}
-
-      - name: UnicodeData cache
-        uses: actions/cache@v4
-        with:
-          path: ${{ github.workspace }}/libjs-test262/Build/caches/UCD
-          key: UnicodeData-${{ hashFiles('Meta/CMake/unicode_data.cmake') }}
-
-      - name: UnicodeLocale cache
-        uses: actions/cache@v4
-        with:
-          path: ${{ github.workspace }}/libjs-test262/Build/caches/CLDR
-          key: UnicodeLocale-${{ hashFiles('Meta/CMake/locale_data.cmake') }}
+          os: 'Linux'
+          arch: 'Lagom'
+          download_cache_path: ${{ github.workspace }}/libjs-test262/Build/caches
 
       - name: Get previous results
         run: |