Fix for gh-2121

[ndgrigorian]

This PR proposes a fix for gh-2121, which is caused by underlying memory of a boolean array not necessarily representing only 0s and 1s, in particular when it is a view from a non-boolean array

This PR adds a path to astype that guarantees astype(a, "?") will give an output array of only 0 and 1

• Have you provided a meaningful PR description?
• Have you added a test, reproducer or referred to an issue with a reproducer?
• Have you tested your changes locally for CPU and GPU devices?
• Have you made sure that new changes do not introduce compiler warnings?
• Have you checked performance impact of proposed changes?
• Have you added documentation for your changes, if necessary?
• Have you added your changes to the changelog?
• If this PR is a work in progress, are you opening the PR as a draft?

[github-actions]

Deleted rendered PR docs from intelpython.github.com/dpctl, latest should be updated shortly. 🤞

[github-actions]

Array API standard conformance tests for dpctl=0.21.0dev0=py310h93fe807_58 ran successfully.
Passed: 1116
Failed: 5
Skipped: 119

[coveralls]

coverage: 85.887% (-0.003%) from 85.89%
when pulling 8e952d1 on resolve-gh-2121
into e2789db on master.

[github-actions]

Array API standard conformance tests for dpctl=0.21.0dev0=py310h93fe807_59 ran successfully.
Passed: 1114
Failed: 7
Skipped: 119

[github-actions]

Array API standard conformance tests for dpctl=0.21.0dev0=py310h93fe807_60 ran successfully.
Passed: 1115
Failed: 6
Skipped: 119

[antonwolfy]

Thank you @ndgrigorian, LGTM!