wait only for the time of the HTTP requests

[mikesmallhelp]

Currently wacat waits by default 5 seconds for every page load or that time can be configured by the wait flag.

Please add functionality that wacat waits only time the network requests are on progress. Perhaps page.waitForNavigation or something like that with the parameter waitUntil and value networkidle could be used. Your solution is enough good if the GitHub actions are passed.