Tests: fix async updates in tests

[matyax]

This PR fixes errors that pollute Jest output, such as:

console.error
      Warning: An update to PatternTag inside a test was not wrapped in act(...).
      
      When testing, code that causes React state updates should be wrapped into act(...):
      
      act(() => {
        /* fire events that update state */
      });
      /* assert on the output */