custom builddir key in config.json in build.webkit.org configuration isn't really required. Buildbot automatically populate it based on builder name. We don't use this key in other buildbot instance. we can delete this.
Pull request: https://github.com/WebKit/WebKit/pull/376
Committed r293325 (249948@main): <https://commits.webkit.org/249948@main> Reviewed commits have been landed. Closing PR #376 and removing active labels.
<rdar://problem/92266445>
Jonathan restarted build.webkit.org to pick this up (along-with https://commits.webkit.org/249946@main). This seems to be working well. bots are using new build directory. Most of apple bots were also configured to automatically delete unused build directories, so old directories were automatically deleted. On other platform, we might want to delete the old build directories manually so as to free up that disk space.