Fix testing step of conda-package workflow

[oleksandr-pavlyk]

Add setuptools to list of packages to be installed into test environment in workflow.

This aligns it with test requirements section of meta.yaml. Setuptools is required by tests that check if an extension can be built using dpctl's headers.

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[oleksandr-pavlyk]

This change fixes error in executing test_linux step in https://github.com/IntelPython/dpctl/actions/runs/10182576343

[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=py310ha798474_192 ran successfully.
Passed: 894
Failed: 1
Skipped: 119

[coveralls]

coverage: 87.609%. remained the same
when pulling 6f59a23 on expand-test-requirement
into 1462d8c on master.