Update GitHub Actions workflow for developer image

Changed workflow name to 'Developer image' and updated triggers and tags for Docker image builds.

Author: indifferentchicken

.github/workflows/developer.yml

@@ -0,0 +1,33 @@
+---
+name: Developer image
+on:
+  push:
+    branches:
+      - main
+jobs:
+  push:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+      - name: Docker - Login
+        uses: docker/login-action@v3
+        with:
+          username: '${{ secrets.DOCKER_USERNAME }}'
+          password: '${{ secrets.DOCKER_PASSWORD }}'
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v3
+      - name: Docker - Metadata
+        id: meta
+        uses: docker/metadata-action@v5
+        with:
+          images: |
+            ${{ github.repository }}
+          tags: 'type=raw,value=dev'
+          flavor: latest=false
+      - name: Docker - Build / Push
+        uses: docker/build-push-action@v6
+        with:
+          platforms: linux/amd64
+          push: true
+          tags: '${{ steps.meta.outputs.tags }}'