[Test] Temporarily disable run-switch-executor.

rdar://problem/72893124

Author: nate-chandler

test/IRGen/async/run-switch-executor.swift

@@ -11,6 +11,8 @@
 // UNSUPPORTED: CPU=arm64e
 // UNSUPPORTED: OS=windows-msvc
 
+// REQUIRES: rdar72893124
+
 // Currently this test just checks if nothing crashes.
 // TODO: also check if the current executor is the correct one.