WebKit only allows one tab to capture at a time, so the SCStream privacy alert is not needed
<rdar://problem/113510677>
Pull request: https://github.com/WebKit/WebKit/pull/16444
Committed 266661@main (52ced8d1a83a): <https://commits.webkit.org/266661@main> Reviewed commits have been landed. Closing PR #16444 and removing active labels.