[CQ] migrate off deprecated loadCoverageData override

[pq]

Migrates to preferred loadCoverageData variation.

See:

https://github.com/JetBrains/intellij-community/blob/16bb6ba35637d311992e86d42ae1a050228c3ee2/plugins/coverage-common/src/com/intellij/coverage/CoverageRunner.java#L27

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