BUG: GH52229 changed code in pandas/pandas/core/reshape/pivot.py _bui…
…ld_names_mapper() to match docstring - replaces names of columns/rows

- [x] closes #52229

Based on the failing test, I think this function just needs to be renamed Thanks for the pull request, but it appears to have gone stale. If interested in continuing, please merge in the main branch, address any review comments and/or failing tests, and we can reopen.