Fix non-symbolic children lookup of fixity declaration
The fix for #23664 (closed) did not correctly account for non-symbolic names when looking up children of a given parent. This one-line fix changes that. Fixes #24037 (closed).
Due to a large amount of spam we do not allow new users to create repositories, they are "external" users. If you are a new user and want to create a repository, for example for forking GHC, open a new issue on ghc/ghc using the "get-verified" issue template
The fix for #23664 (closed) did not correctly account for non-symbolic names when looking up children of a given parent. This one-line fix changes that. Fixes #24037 (closed).