gitea, gogs: Ensure query parameters are not duplicated in API URLs

Gitea API return next pagination link with all query parameters provided
to an API request.

As we were also passing a dict of fixed query parameters to the page_request
method, some query parameters ended up having multiple instances in the URL
for fetching a new page of repositories data. So each time a new page was
requested, new instances of these parameters were appended to the URL which
could result in a really long URL if the number of pages to retrieve is high
and make the request fail.

Also remove a debug log already present in http_request method.