10230 work around bpo-44070 by making filenames absolute before calling spec_from_file_location

[graingert]

Scope and purpose

fix test_moduleNotInPath and test_packageNotInPath as well as their TODOs'

Contributor Checklist:

• The associated ticket in Trac is here: https://twistedmatrix.com/trac/ticket/10230
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Merge pull request #123 from twisted/4356-branch-name-with-trac-id

Author: <github_username>, <github_usernames_if_more_authors>
Reviewer: <github_username>, <github_username_if_more_reviewers>
Fixes: ticket:<trac_ticket_number>, ticket:<another_if_more_in_one_PR>

Long description providing a summary of these changes.
(as long as you wish)

[graingert]

https://bugs.python.org/issue44070

[graingert]

https://www.irccloud.com/pastebin/Yx1hHCUh/3.8.10.pdb
https://www.irccloud.com/pastebin/63ckKfI3/3.9.6.pdb

10:34:11 <graingert> https://www.irccloud.com/pastebin/Yx1hHCUh/3.8.10.pdb
10:34:27 <graingert> https://www.irccloud.com/pastebin/63ckKfI3/3.9.6.pdb
10:34:52 <graingert> ModuleSpec(name='test_sample', loader=<_frozen_importlib_external.SourceFileLoader object at 0x7f0b8eb7fd00>, origin='twisted.trial.test.test_loader/FileTests/test_moduleNotInPath/ygwayv_e/temp/goodpackage/test_sample.py') is different from how the actual "import " keyword works adiroiban 
10:35:42 <graingert> I think on 3.8+ we're responsible for abspathing the path to spec_from_file_location
10:35:48 <graingert> but I'm not sure

[graingert]

part of "properly import and return that package." is adding the package to sys.modules

[adiroiban]

but isn't import goodpackage doing the same thing?
just asking :)

[graingert]

import goodpackage will set the "goodpackage" in sys.modules key if we forgot to set it

[adiroiban]

All good. Thanks for the quick fix.

Only a minor comment regarding the release notes.

[adiroiban]

Minor comment...
I am not 100% I understand this release note.

Suggested change

	trial.runner.filenameToModule now sets the correct module.__name__ and sys.modules key
	trial.runner.filenameToModule now sets an absolute path to the module when updating module.__name__ and sys.modules key

[graingert]

This PR fixes the whole module.__spec__. before the algorithm only got the module.__file__ correct on 3.7- and 3.10+

The module.__name__ was set incorrectly as the stem of the path passed to filenameToModule