ci(api): update actions to latest version

.github/workflows/api-push.yaml

@@ -12,12 +12,18 @@ jobs:
     steps:
       - name: Check out repo
         uses: actions/checkout@v2
-      - name: Build and push API
-        uses: docker/build-push-action@v1
+      - name: Login to GitHub registry
+        uses: docker/login-action@v1
         with:
-          context: api
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
           registry: docker.pkg.github.com
-          repository: engineer-man/piston/piston-api
-          tag_with_ref: true
+
+      - name: Build and push API
+        uses: docker/build-push-action@v2
+        with:
+          context: api
+          push: true
+          repository: 
+          tags: |
+            docker.pkg.github.com/engineer-man/piston-api