docs: FlutterFire link to point to main branch

Author: spydon

docs/getting-started.mdx

@@ -159,7 +159,7 @@ Then execute the command by running `melos generate`.
 
 If you're looking for some inspiration as to what scripts can help with, check
 out the
-[FlutterFire repository](https://github.com/firebase/flutterfire/blob/master/melos.yaml)
+[FlutterFire repository](https://github.com/firebase/flutterfire/blob/main/melos.yaml)
 or the [Flame repository](https://github.com/flame-engine/flame/blob/main/melos.yaml).
 
 If you are using VS Code, there is an [extension](/ide-support#vs-code)