clone: use "official" API to create local clone destination This make sure we have a properly created, fully functional repository early. This will be useful to simply the hardlink/copy phases of the local clone to make it share more of its logic with the similar "stream" cloning. This has a minor impact of the test and the resulting repository has is better initialized (eg: the `wcache` directory is pre-created.) Differential Revision: https://phab.mercurial-scm.org/D10850

localrepo: introduce a clone_requirements function This function take a source repository and return a relevant set of requirements that should be used by a copy clone. This will help make the creation of the destination repository during copy clone simpler. Differential Revision: https://phab.mercurial-scm.org/D10849

createrepository: allow to directly pass the target requirements This is useful when doing a local clone that copies store contents, it will requires the destination to use the very same store requirements so directly providing them will be simpler and safer Differential Revision: https://phab.mercurial-scm.org/D10848

narrowbundle: use new context manager for silencing the ui Same reasoning as the previous change. This affects a few tests because of the hack from d7304434390f (changegroup: move message about added changes to transaction summary, 2019-09-08). Differential Revision: https://phab.mercurial-scm.org/D10886