Update README for wheel installation

[DenisScherbakov]

wheel package is published on PyPi and on pypi.anaconda.org.
README is part of wheel metadata which is published on PyPi and this update is needed to specify
pypi.anaconda.org as recommended installation channel.

• 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?
• If this PR is a work in progress, are you opening the PR as a draft?

[github-actions]

View rendered docs @ https://intelpython.github.io/dpctl/pulls/1353/index.html

[coveralls]

coverage: 85.041%. remained the same when pulling 1468978 on fix/install into 9c18949 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.14.6dev3=py310ha25a700_15 ran successfully.
Passed: 913
Failed: 87
Skipped: 119

[github-actions]

Array API standard conformance tests for dpctl=0.14.6dev3=py310ha25a700_17 ran successfully.
Passed: 913
Failed: 87
Skipped: 119

[github-actions]

Array API standard conformance tests for dpctl=0.14.6dev3=py310ha25a700_18 ran successfully.
Passed: 913
Failed: 87
Skipped: 119

[github-actions]

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