Relay 13 compiler doesn't delete stale codegen

[arcticmatt]

For example, let's say I have Foo.tsx, which contains a GraphQL mutation called FooMutation. This will cause Relay compiler to generate a file called FooMutation.graphql.ts

However, if I delete FooMutation from Foo.tsx, and then re-run the Relay compiler, FooMutation.graphql.ts will still be there. I expected it to be deleted