Add GHCR perms to CI and pin Action versions

.github/workflows/push-docker.yml

@@ -5,12 +5,14 @@ on:
     branches: 
       - master
       - main
+
 jobs:
   push:
-
     runs-on: ubuntu-latest
+    permissions:
+      packages: write
+      contents: read
     steps:
-
     - uses: actions/checkout@v3
     
     - name: Set up JDK 17
@@ -18,7 +20,6 @@ jobs:
       with:
         java-version: '17'
         distribution: 'temurin'
-    
 
     - uses: gradle/gradle-build-action@v2.3.3
       with:
@@ -39,7 +40,7 @@ jobs:
         password: ${{ secrets.DOCKER_HUB_API }}
         
     - name: Login to GitHub Container Registry
-      uses: docker/login-action@v2
+      uses: docker/login-action@v2.1.0
       with:
         registry: ghcr.io
         username: ${{ github.actor }}
@@ -47,7 +48,7 @@ jobs:
 
     - name: Generate tags
       id: meta
-      uses: docker/metadata-action@v4
+      uses: docker/metadata-action@v4.4.0
       with:
         images: |
           frooodle/s-pdf
@@ -56,13 +57,13 @@ jobs:
           ${{ steps.versionNumber.outputs.versionNumber }}${{ github.ref == 'refs/heads/main' && '-alpha' || '' }}
    
     - name: Set up QEMU
-      uses: docker/setup-qemu-action@v2
+      uses: docker/setup-qemu-action@v2.1.0
       
     - name: Set up Docker Buildx
-      uses: docker/setup-buildx-action@v2
+      uses: docker/setup-buildx-action@v2.5.0
         
     - name: Build and push
-      uses: docker/build-push-action@v4
+      uses: docker/build-push-action@v4.0.0
       with:
         push: true
         tags: ${{ steps.meta.outputs.tags }}