DetermineLabelName is conditioned on the wrong bot for label owner status. Add 'webkit-ews-buildbot'.
<rdar://problem/115502038>
Pull request: https://github.com/WebKit/WebKit/pull/17776
Committed 268006@main (1b5102284c60): <https://commits.webkit.org/268006@main> Reviewed commits have been landed. Closing PR #17776 and removing active labels.