Added entry to changelog for 0.18.1

[oleksandr-pavlyk]

Backport changes to CHANGELOG.md made in maintenance/0.18.x branch

• 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?
• Have you added documentation for your changes, if necessary?
• Have you added your changes to the changelog?
• If this PR is a work in progress, are you opening the PR as a draft?

[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=py310hdf72452_147 ran successfully.
Passed: 894
Failed: 1
Skipped: 119

[coveralls]

coverage: 87.673%. remained the same
when pulling 95dd373 on backport-changelog-0-18-1
into 9eb8f03 on master.