gh-99352: Respect `http.client.HTTPConnection.debuglevel` in `urllib.request.AbstractHTTPHandler` (#99353)

* bugfix: let the HTTP- and HTTPSHandlers respect the value of http.client.HTTPConnection.debuglevel

* add tests

* add news

* ReSTify NEWS and reword a bit.

* Address Review Comments.

* Use mock.patch.object instead of settting the module level value.
* Used test values to assert the debuglevel.

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Co-authored-by: Gregory P. Smith <greg@krypto.org>
Co-authored-by: Senthil Kumaran <senthil@python.org>