Reduced specificity of select class in css

[rohanthacker]

Did you search for similar issues before submitting this one?
Yes
Describe the issue you encountered:
The style of select element used is deeply nested under settings

Expected behavior:
Reduce code duplications by assigning classes, similar to the pattern used in other elements, For Eg : button.

• Platform (Win7, 8, 10? macOS? Linux distro?):
  All
• Brave Version:
  11.3
• Steps to reproduce:
  1. Improve UI/UX of bookmark popup #2894 , Required Dropdown for Bookmarks
  2. Select Element used in Brave Menu
  

3.Select Element Used in Settings, similar to bookmarks but nested under settings classes.

[bradleyrichter]

the brave menu should ideally use the in-page style for popup menus.