docs(Notify): fix z-index option case

[chenjiahan]

options should be camelcase

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 89.72%. Comparing base (168728e) to head (43ee790).
Report is 3 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #12919      +/-   ##
==========================================
- Coverage   89.73%   89.72%   -0.02%     
==========================================
  Files         257      257              
  Lines        6975     6975              
  Branches     1718     1718              
==========================================
- Hits         6259     6258       -1     
  Misses        379      379              
- Partials      337      338       +1     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.