Remove the wheels installation with anaconda from the instruction

[ekomarova]

This PR removes the wheels installation with Anaconda from the instruction, since we will no longer be able to upload packages to Anaconda. And so far, wheels can only be uploaded on Pypi

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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=0.18.0dev0=py310hdf72452_384 ran successfully.
Passed: 894
Failed: 1
Skipped: 119

[coveralls]

coverage: 87.9%. remained the same
when pulling f0484c1 on wheels/update_readme
into 856615d on master.

[oleksandr-pavlyk]

@ekomarova There are also mentions in docs/doc_sources/beginners_guides/installation.rst. Could you fix those too, please?

[oleksandr-pavlyk]

Thank you @ekomarova ! LGTM

[github-actions]

Array API standard conformance tests for dpctl=0.18.0dev0=py310hdf72452_384 ran successfully.
Passed: 894
Failed: 1
Skipped: 119