[libcxx][test][AIX] address more platform differences in locale tests (#94826)

This is a follow on to https://github.com/llvm/llvm-project/pull/92312,
where we address some more locale platform differences. These are:

- for locale fr_FR AIX libc expects `U202F` as `LC_MONETARY`
- for locale zh_CN AIX libc `LC_MONETARY` has `n_sign_posn == 1`,
indicating the `negative_sign` should come before the `currency_symbol`

GitOrigin-RevId: 9afb09e674d6195faf09431dda8a3a08886ab27d
4 files changed