Fix tests & linter

[philipp-classen]

Tests are working with Node 14, but fail on Node 16. Maybe there are more reasons, but one is that the code does not always handle rejected promises.

The linter is currently also complaining on master ("warning Unexpected unnamed function func-names").

[philipp-classen]

The integration tests appear to be flaky, but it is hard to understand the pattern. Rerunning tests on the CI does not seem to change the results, which would normally be expected for most types of races or timeouts.

Locally, main fails consistently for me because "chrome.history.onVisited" is not available. On the CI, it is not always reproducible (and repeat does not change anything). Maybe the order in which tests are run makes a difference?

Locally, these changes fix the integration tests: #41

[philipp-classen]

Has been fixed in the meantime: the tests are working now with 14, 16, 18