Update deploy action (#95)

- Bump actions/checkout from v3 to v4

Author: jbakerdev

.github/workflows/deploy.yml

@@ -14,7 +14,7 @@ jobs:
       name: production
       url: https://jbaker.dev
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
       - uses: superfly/flyctl-actions/setup-flyctl@master
       - run: flyctl deploy --remote-only
         env: