AnnotationTypeMapping.addConventionMappings() sometimes adds
convention-based mappings that it should not.
For example, in certain circumstances an explicit annotation attribute
override configured via @AliasFor can be incorrectly mapped as
convention-based.
Although this does not appear to cause negative side effects (other
than unnecessary processing), this is technically a bug, and this
commit address this issue.
Closes gh-28773
81acbe7e2f