Remove stubs for urllib3

[AlexWaygood]

Fixes #6898.
Fixes #10142.

Note that this has a significant impact on the number of stubs packages with non-types dependencies. Both types-requests and types-influxdb-client now depend on urllib3>=2 instead of types-urllib3. That in turn means that types-caldav, types-slumber and types-requests-oauthlib all depend indirectly on urllib3, since all three stubs packages depend on types-requests. All of that might mean that mypy_test.py and regr_test.py slow down a bit. If so, I have some ideas for mitigations I could work on in future PRs for speeding them up a bit.

[AlexWaygood]

N.B. I checked stubtest for types-caldav, types-slumber and types-requests-oauthlib all locally; everything was green

[AlexWaygood]

All of that might mean that mypy_test.py and regr_test.py slow down a bit.

Looks like regr_test.py in particular gets a bit slower, but nothing too catastrophic :)

[github-actions]

Diff from mypy_primer, showing the effect of this PR on open source code:

pwndbg (https://github.com/pwndbg/pwndbg)
+ pwndbg/commands/ai.py:16: note: ... from here:
+ pwndbg/commands/ai.py:16: note: ... from here:
+ pwndbg/commands/ai.py:16: note: ... from here:
+ pwndbg/commands/ai.py:16: note: ... from here: