test(tearsheet): implement AVT coverage for complex functionalities

[makafsal]

Closes #5521

What did you change?

1. Focus trap and focus return to launcher button

How did you test and verify your work?

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[elycheea]

FYI, noticed the AVT tests aren’t actually running for Tearsheet in our CI. Checked with @matthewgallo and @davidmenendez and I think we may just need to add some more avt runners.