browser test: wait for token request to finish before reloading

[minrk]

this may be the cause of flaky tests where there are no tokens to list

This might fix failures like this one in test_revoke_token[request_by_user]:

        if token_type in {"server_up", "request_by_user"}:
>           await expect(revoke_btns).to_have_count(1)
E           AssertionError: Locator expected to have count '1'
E           Actual value: 0 
E           Call log:
E           LocatorAssertions.to_have_count with timeout 5000ms

where the failure suggests that the token wasn't actually requested, and the logs appear to confirm that the request for a new token is not received by the server. My hunch is that awaiting the button click doesn't await the resulting fetch, and reloading the page prevents it from actually firing. A second option is that the javascript click event isn't hooked up before we trigger the click, so clicking doesn't do anything.

[minrk]

@meeseeksdev backport to 4.x