Release process: no reason to wait for 1+ hour for non-final releases

The idea was that we have to wait long enough before announcing a new release, such that browser caches won't be a problem. However, for non-final (M and RC) releases, that is not needed. They are deployed to new URLs, rather than to the standard visible website. Hence, the browser cache problem isn't there for those releases. We do need to wait until the website is deployed from the ESCET website Git repo to the webserver, but that only takes a few minutes.