REF: re-use _maybe_promote for _is_convertible_to_index_for_join (#36416)
REF: re-use _maybe_promote for _is_convertible_to_index_for_join (#36416)


dsm054/pandas,jreback/pandas,pandas-dev/pandas,gfyoung/pandas,gfyoung/pandas,jorisvandenbossche/pandas,datapythonista/pandas,gfyoung/pandas,datapythonista/pandas,rs2/pandas,rs2/pandas,jreback/pandas,pandas-dev/pandas,jreback/pandas,jorisvandenbossche/pandas,jorisvandenbossche/pandas,jreback/pandas,jreback/pandas,rs2/pandas,gfyoung/pandas,pandas-dev/pandas,dsm054/pandas,datapythonista/pandas,datapythonista/pandas,rs2/pandas,gfyoung/pandas,dsm054/pandas,jorisvandenbossche/pandas,dsm054/pandas,dsm054/pandas,pandas-dev/pandas