Attempt to cache yarn dependencies in GitHub cache

.github/workflows/docker-vue3.yml

@@ -5,6 +5,9 @@ on:
     branches:
       - 'vue3'
 
+env:
+  TAG: facilmap/facilmap:vue3
+
 jobs:
   push_to_registry:
     name: Push Docker image to Docker Hub
@@ -13,6 +16,15 @@ jobs:
       -
         name: Checkout
         uses: actions/checkout@v4
+
+      # Set up yarn cache
+      - name: Set up Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '21'
+          cache: 'yarn'
+
+      # Build docker image
       -
         name: Set up QEMU
         uses: docker/setup-qemu-action@v3
@@ -32,6 +44,10 @@ jobs:
         with:
           push: true
           context: .
-          tags: facilmap/facilmap:vue3
+          tags: ${{env.TAG}}
           cache-from: type=gha
-          cache-to: type=gha,mode=max
+          cache-to: type=gha,mode=max
+
+      -
+        name: Populate Yarn cache
+        run: rm -f .yarn/cache/* && docker cp "$(docker create "$TAG"):/opt/facilmap/.yarn/cache/." .yarn/cache/ && ls .yarn/cache