Fix representation for builtin function types.

[kschwab]

Change Summary

Fixes representation of builtin function types evaluated in display_as_type function.

Related issue number

Fixes #10228

Checklist

• The pull request title is a good summary of the changes - it will be used in the changelog
• Unit tests for the changes exist
• Tests pass on CI
• Documentation reflects the changes where applicable
• My PR is ready to review, please add a comment including the phrase "please review" to assign reviewers

[codspeed-hq]

CodSpeed Performance Report

Merging #10479 will not alter performance

_{Comparing kschwab:builtin-function-repr (afd8e55) with main (43ed0d3)}

Summary

✅ 38 untouched benchmarks

[github-actions]

Coverage report

Click to see where and how coverage changed

File	Statements	Missing	Coverage	Coverage (new stmts)	Lines missing
pydantic/_internal
_repr.py
Project Total

This report was generated by python-coverage-comment-action

[sydney-runkle]

Looks good, thanks for the fix :)