Fix spurious sqlite e2e test failure

[MasterOdin]

When running test:e2e, I was finding that the sqlite test was failing some amount of the time on:

    await helper.expectToEqualText(
      mainWindow,
      '.react-tabs__tab-panel--selected .ace_content',
      'SELECT * FROM "document" LIMIT 101',
    );

Where the amount of time taken to load the results was just long enough between the prior click and then running this line that it would fail. As we cannot add a timeout on this particular line, easier to add a waitForSelector for some other part of the UI that changes (in this case the query results table appearing) to achieve that goal, and improve stability on this test.