Fix a typo in documentation

[antonwolfy]

This PR updates docstrings of from_numpy and astype functions to remove a duplicating a in description of device keyword.

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[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=0.19.0dev0=py310h93fe807_529 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[coveralls]

coverage: 88.224%. remained the same
when pulling 3a059aa on fix-type-in-docs
into 0a9c725 on master.