Disabling main resolution tests

Disabling these tests until I figure out how to fix the async-main
resolution.

Author: etcwilde

test/Concurrency/async_main_resolution.swift

@@ -6,6 +6,8 @@
 // sync main is nested deeper in protocols than async, use async
 // async and sync are same level, use async
 
+// REQUIRES: rdar89500797
+
 // REQUIRES: concurrency
 // UNSUPPORTED: VENDOR=apple
 

test/Concurrency/async_main_resolution_macos.swift

@@ -2,6 +2,8 @@
 // sync main is nested deeper in protocols than async, use async if supported
 // async and sync are same level, use async if supported
 
+// REQUIRES: rdar89500797
+
 // async main is nested in the protocol chain from `MyMain`
 // Always choose Sync overload
 // RUN: %target-swift-frontend -target x86_64-apple-macosx10.9 -DASYNC_NESTED -DINHERIT_SYNC -typecheck -dump-ast -parse-as-library %s | %FileCheck %s --check-prefix=CHECK-IS-SYNC