feat(cd): use semantic release for docker images

.github/workflows/main.yml

@@ -1,43 +0,0 @@
-on:
-  push:
-    branches:
-      - master
-  workflow_dispatch:
-
-jobs:
-
-  build:
-    name: Build, push, and deploy
-    runs-on: ubuntu-latest
-    steps:
-
-    - name: Checkout master
-      uses: actions/checkout@v2
-
-    - name: Build PostgreSQL container image
-      run: |
-        docker build --build-arg DATABASE_TYPE=postgresql \
-        --tag ghcr.io/$GITHUB_ACTOR/umami:postgresql-${github.ref_name} \
-        --tag ghcr.io/$GITHUB_ACTOR/umami:postgresql-latest \
-        .
-
-    - name: Build MySQL container image
-      run: |
-        docker build --build-arg DATABASE_TYPE=mysql \
-        --tag ghcr.io/$GITHUB_ACTOR/umami:mysql-${github.ref_name} \
-        --tag ghcr.io/$GITHUB_ACTOR/umami:mysql-latest \
-        .
-
-    - name: Docker login
-      run: >-
-        echo "${{ secrets.GITHUB_TOKEN }}"
-        | docker login -u "${{ github.actor }}" --password-stdin ghcr.io
-      
-    - name: Push image to GitHub
-      run: |
-        # Push each image individually, avoiding pushing to umami:latest
-        # as MySQL or PostgreSQL are required
-        docker push ghcr.io/$GITHUB_ACTOR/umami:postgresql-${github.ref_name}
-        docker push ghcr.io/$GITHUB_ACTOR/umami:postgresql-latest
-        docker push ghcr.io/$GITHUB_ACTOR/umami:mysql-${github.ref_name}
-        docker push ghcr.io/$GITHUB_ACTOR/umami:mysql-latest