Add GitHub Actions workflow for building Docker image

.gitea/workflows/build.yml

@@ -0,0 +1,16 @@
+name: Build Docker Image
+on:
+  push:
+    branches:
+      - main
+
+jobs:
+  build:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v2
+
+      - name: Build Docker image
+        run: |
+          docker build -t skoszewski/azure-cli:latest .