Add fly deployment action

.github/workflows/fly-deploy.yml

@@ -0,0 +1,21 @@
+name: Deploy to Fly
+
+on:
+  push:
+      branches: [main]
+
+env:
+  FLY_API_TOKEN: ${{ secrets.FLY_API_TOKEN }}
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+      - name: Checkout 
+        uses: actions/checkout@v2
+
+      - name: Setup Fly
+        uses: superfly/flyctl-actions/setup-flyctl@master
+      
+      - name: Deploy
+        run: flyctl deploy