Bump actions/cache from 3 to 4 (heroku#686)

Bumps [actions/cache](https://github.com/actions/cache) from 3 to 4.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v3...v4)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

.github/workflows/platform-build.yml

@@ -68,7 +68,7 @@ jobs:
         uses: actions/checkout@v4
       - name: Cache Docker build
         id: cache-docker
-        uses: actions/cache@v3
+        uses: actions/cache@v4
         with:
           key: docker-cache-heroku-php-build-${{inputs.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz
@@ -93,7 +93,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Restore cached Docker build
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: docker-cache-heroku-php-build-${{inputs.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz
@@ -119,7 +119,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Restore cached Docker build
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: docker-cache-heroku-php-build-${{inputs.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz

.github/workflows/platform-remove.yml

@@ -40,7 +40,7 @@ jobs:
           echo ${{inputs.manifests}} | xargs -n 1 echo - >> "$GITHUB_STEP_SUMMARY"
       - name: Restore cached Docker image
         id: restore-docker
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: docker-cache-heroku-php-build-${{inputs.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz
@@ -55,7 +55,7 @@ jobs:
         run: docker save heroku-php-build-${{inputs.stack}}:${{github.sha}} | gzip -1 > /tmp/docker-cache.tar.gz
       - name: Cache built Docker image
         if: steps.restore-docker.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v3
+        uses: actions/cache/save@v4
         with:
           key: ${{ steps.restore-docker.outputs.cache-primary-key }}
           path: /tmp/docker-cache.tar.gz

.github/workflows/platform-sync.yml

@@ -53,7 +53,7 @@ jobs:
         uses: actions/checkout@v4
       - name: Restore cached Docker image
         id: restore-docker
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: docker-cache-heroku-php-build-${{matrix.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz
@@ -68,7 +68,7 @@ jobs:
         run: docker save heroku-php-build-${{matrix.stack}}:${{github.sha}} | gzip -1 > /tmp/docker-cache.tar.gz
       - name: Cache built Docker image
         if: steps.restore-docker.outputs.cache-hit != 'true'
-        uses: actions/cache/save@v3
+        uses: actions/cache/save@v4
         with:
           key: ${{ steps.restore-docker.outputs.cache-primary-key }}
           path: /tmp/docker-cache.tar.gz
@@ -85,7 +85,7 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
       - name: Restore cached Docker build
-        uses: actions/cache/restore@v3
+        uses: actions/cache/restore@v4
         with:
           key: docker-cache-heroku-php-build-${{matrix.stack}}.${{github.sha}}
           path: /tmp/docker-cache.tar.gz