fix: Fix the workspace-search plugin tests

[gonfunko]

The basics

• I validated my changes

The details

Proposed Changes

This PR fixes the tests for the workspace-search plugin. There were two issues:

• At some point, we changed the behavior to allow the workspace to be directly focusable rather than focusing the first block. The tests were expecting the latter behavior; I updated them to expect and verify the former.
• Things weren't being cleaned up and timers were firing after test teardown, causing a failure to be reported even though all testcases were passing.