use ruby 3.0 for dpl v2 and update tag naming and dockerfile

.github/workflows/docker-image.yml

@@ -3,26 +3,30 @@ name: Docker Build and Push
 on:
   push:
     branches:
-      - master  # Set your default branch here
+      - master
       - pre
 
+env:
+  RUBY_VERSION: '3.0' # Define the Ruby version here
+
 jobs:
   build-and-push:
     runs-on: ubuntu-latest
     steps:
-    - name: Check Out Repo
-      uses: actions/checkout@v2
+      - name: Check Out Repo
+        uses: actions/checkout@v2
 
-    - name: Log in to Docker Hub
-      uses: docker/login-action@v1
-      with:
-        username: ${{ secrets.DOCKER_HUB_USERNAME }}
-        password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
+      - name: Log in to Docker Hub
+        uses: docker/login-action@v1
+        with:
+          username: ${{ secrets.DOCKER_HUB_USERNAME }}
+          password: ${{ secrets.DOCKER_HUB_ACCESS_TOKEN }}
 
-    - name: Build and Push Docker Image
-      uses: docker/build-push-action@v2
-      with:
-        context: .
-        file: Dockerfile
-        push: true
-        tags: dreamteammobile/gitlab-runner-heroku-dpl:${{ github.ref == 'refs/heads/pre' && 'v2' || 'latest' }}
+      - name: Build and Push Docker Image
+        uses: docker/build-push-action@v2
+        with:
+          context: .
+          file: Dockerfile
+          push: true
+          tags: dreamteammobile/gitlab-runner-heroku-dpl:${{ github.ref == 'refs/heads/pre' && 'v2' || 'v1' }}_${{ env.RUBY_VERSION }}
+          build-args: RUBY_VERSION=${{ env.RUBY_VERSION }}

Dockerfile

@@ -1,4 +1,4 @@
-FROM ruby:2.7.5-alpine
+ARG RUBY_VERSION
+FROM ruby:${RUBY_VERSION}-alpine
 RUN apk --no-cache add git curl
 RUN gem install dpl --pre
-