[ews] Use separate log category for results database logs in buildbot builds (while checking if the test failures are pre-existing or not).
<rdar://problem/102860428>
Pull request: https://github.com/WebKit/WebKit/pull/7024
Committed 257240@main (38e349d1441c): <https://commits.webkit.org/257240@main> Reviewed commits have been landed. Closing PR #7024 and removing active labels.