Add deprecation alert for notification categories

[zacwest]

Summary

Alerts if there are any notification categories (local or synced) if the user is an admin on any of their servers.

The configuration is marked as deprecated in home-assistant/core#61078 and will produce warnings until it's removed from there as well.

Screenshots

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Link to pull request in Documentation repository

Documentation: home-assistant/companion.home-assistant#

Any other notes

[codecov]

Codecov Report

Merging #1976 (112084f) into master (06f65be) will decrease coverage by 0.04%.
The diff coverage is 0.00%.

@@            Coverage Diff             @@
##           master    #1976      +/-   ##
==========================================
- Coverage   29.05%   29.01%   -0.05%     
==========================================
  Files         268      268              
  Lines       20923    20954      +31     
==========================================
- Hits         6080     6079       -1     
- Misses      14843    14875      +32     

Impacted Files	Coverage Δ
Sources/App/AppDelegate.swift	8.49% <0.00%> (-0.79%)	⬇️
...rces/Shared/Common/Extensions/URL+Extensions.swift	38.70% <0.00%> (-3.23%)	⬇️

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