We no longer need to build with Xcode versions which didn't support LTO (with the exception of JavaScriptCore, which had issues for longer).
<rdar://problem/106580397>
Pull request: https://github.com/WebKit/WebKit/pull/11394
Committed 261576@main (3b79ec17d4e1): <https://commits.webkit.org/261576@main> Reviewed commits have been landed. Closing PR #11394 and removing active labels.