Pull screen search feature

[kirtangajjar]

Description of the Change

Add ability to search for a site on the Pull Content screen

Closes #1235

How to test the Change

Changelog Entry

Added - Ability to search for a site on pull content screen

Credits

Props @kirtangajjar

Checklist:

• [x] I agree to follow this project's Code of Conduct.
• [x] I have updated the documentation accordingly.
• [x] I have added tests to cover my change.
• [x] All new and existing tests pass.