Allow both urllib3 1 and urllib3 2 in the kubernetes python package

[gibsondan]

What is the feature and why do you need it:
27459d5 implies that the urllib3 pin was added because google-auth doesn't support urllib3 2. However, as of the latest release earlier this week, google-auth now supports that version: googleapis/google-auth-library-python#1389 (comment) (in fact, it has a lower bound pin, although they are in the process of changing that). I believe that change can now be reverted.

Describe the solution you'd like to see:
The kubernetes package supporting both urllib3 1 and urllib3 2.