Language selector removes anchor ID from URL when switching between languages

1. Bug: When viewing a page with any anchor ID (e.g., #internal-projects-and-groups) and switching languages using the language selector, the anchor is dropped and a user is taken to the top of the page instead of staying on the same section / anchor ID in a different language
2. Where: any page with anchor IDs
3. Reproduce: Go to any docs page with an anchor ID in the URL, switch to Japanese using the language selector, and observe that the URL loses the anchor and jumps the user to the top of the page
4. Browser/device: https://whatismybrowser.com/w/CSXRCFC
5. Expected: when language switching, preserve the anchor ID, so that user stays at the same section in the new language
6. Severity: Medium