Add share server to server settings fragment using my website

[TimoPtr]

Summary

Add a share button in the server settings screen.

Checklist

• [ ] New or updated tests have been added to cover the changes following the testing guidelines.
• [x] The code follows the project's code style and best_practices.
• [x] The changes have been thoroughly tested, and edge cases have been considered.
• [x] Changes are backward compatible whenever feasible. Any breaking changes are documented in the changelog for users and/or in the code for developers depending on the relevance.

Screenshots

Any other notes

Should be merged after https://github.com/home-assistant/android/pull/5425