[Distributed] Disable test on watchos as 5.7 seems to have some missing cherry-picks

Author: ktoso

test/Distributed/Runtime/distributed_actor_init_local.swift

@@ -8,6 +8,10 @@
 // UNSUPPORTED: use_os_stdlib
 // UNSUPPORTED: back_deployment_runtime
 
+// FIXME(distributed): 5.7 branches seem to be missing something; as `main + 32bit watch` does not crash on DA usage with the local testing actor system, but 5.7 does.
+// rdar://92952551
+// UNSUPPORTED: OS=watchos
+
 import Distributed
 
 enum MyError: Error {