Fix warnings in coverage builds

[ndgrigorian]

This PR proposes fixing warnings which have appeared for uninitialized variables in Coverage builds

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[github-actions]

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

[coveralls]

coverage: 74.797%. remained the same — fix-coverage-build-warnings into master

[antonwolfy]

The coverage build is now free of source-code warnings, and CI is green