chore(gitpod): fix an spelling bug on checkoutLocation

This was the reason why our custom VS Code workspace didn't work.

.gitpod.yml

@@ -1,5 +1,5 @@
 # We're gonna customize the checkout location a bit.
-checkoutLocation: rtaapp-verify
+checkoutLocation: rtapp-verify
 # Also use our custom Code Workspace for Gitpod. Feel free to use it in VS Code, Theia
 # or even code-server if you want.
 workspaceLocation: rtapp-verify/rtapp-verify.code-workspace