add symlink for FVM in GitHub Actions workflow

Author: jperezrealini

.github/workflows/dart.yml

@@ -27,6 +27,11 @@ jobs:
         with:
           flavor: ${{ matrix.channel }}
 
+      - name: Create FVM symlink for melos
+        run: |
+          mkdir -p .fvm
+          ln -s "$(dirname $(which flutter))/.." .fvm/flutter_sdk
+
       - name: Install dependencies
         run: |
           dart pub global activate melos