[MAINT] Unpin conda-build

[ndgrigorian]

This PR proposes unpinning conda-build in the conda-package workflow, as well as updating the workflow to account for conda-build (after 25.1.0) moving to producing .conda files instead of tarballs.

The change to .conda files is motivated by improvements to package compression, which bring dpctl from ~24 MB to ~13.5 MB, about a 40% decrease in size.

• Have you provided a meaningful PR description?
• Have you added a test, reproducer or referred to an issue with a reproducer?
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• Have you made sure that new changes do not introduce compiler warnings?
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[github-actions]

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

[coveralls]

coverage: 88.24%. remained the same
when pulling c612f93 on permit-conda-build-25-1-1
into 7bc3d80 on master.

[github-actions]

Array API standard conformance tests for dpctl=0.19.0dev0=py310h93fe807_499 ran successfully.
Passed: 894
Failed: 2
Skipped: 118

[antonwolfy]

LGTM

[oleksandr-pavlyk]

PR is lacking description of intent of the change. Is the reason for the change to produce .conda artifacts, or is the change to .conda consequence of updating version of conda-build, which was on a to-do list for some time?

[ndgrigorian]

PR is lacking description of intent of the change. Is the reason for the change to produce .conda artifacts, or is the change to .conda consequence of updating version of conda-build, which was on a to-do list for some time?

Yes, great point, I'll fix that by adding a PR description. :)

It's a consequence of the workflow using conda-build 25.1.1, which produces .conda instead of tarballs by default. The reason is apparently due to improved compression.

[ndgrigorian]

For example of the compression, before:

after: