Adapt postgres-baskup-s3 to backup Docker volumes instead of Postgres databases

.github/workflows/build-push.yml

@@ -1,22 +1,13 @@
-name: build and push images
+name: Build and push image
 
 on:
   push:
-    branches: ['master']
+    branches: ['main']
 
 jobs:
   build-and-push-image:
     runs-on: ubuntu-latest
 
-    strategy:
-      matrix:
-        include:
-          - { postgres: 12, alpine: '3.12' }
-          - { postgres: 13, alpine: '3.14' }
-          - { postgres: 14, alpine: '3.16' }
-          - { postgres: 15, alpine: '3.17' }
-          - { postgres: 16, alpine: '3.19' }
-
     steps:
       - name: Checkout repository
         uses: actions/checkout@v2
@@ -38,9 +29,7 @@ jobs:
         with:
           context: .
           push: true
-          tags: ${{ github.repository }}:${{ matrix.postgres }}
-          build-args: |
-            ALPINE_VERSION=${{ matrix.alpine }}
+          tags: ${{ github.repository }}:latest
           platforms: |
             linux/amd64
             linux/arm64