Fix for bug when creating folders or files using New+ within folders that contain Unicode character (wstring all the way)

[cgaarden]

Summary of the Pull Request

Fixed mistaken usage of std::string with std::wstring

PR Checklist

• [x] Closes: #35357
• [x] Communication: I've discussed this with core contributors already. If work hasn't been agreed, this work might be rejected
• [n/a] Tests: Added/updated and all pass
• [n/a] Localization: All end user facing strings can be localized
• [n/a] Dev docs: Added/updated
• [n/a] New binaries: Added on the required places
  • [n/a] JSON for signing for new binaries
  • [n/a] WXS for installer for new binaries and localization folder
  • [n/a] YML for CI pipeline for new test projects
  • [n/a] YML for signed pipeline
• [n/a] Documentation updated: If checked, please file a pull request on our docs repo and link it here: #xxx

Detailed Description of the Pull Request / Additional comments

Fixed mistaken usage of std::string with std::wstring

Validation Steps Performed

1. Created folders and files using New+ in non-Unicode named folders
2. Created folders and files using New+ in Unicode named folder ("Hebrew alphabet אָלֶף־בֵּית עִבְרִ")