Disable custom_rr_abi.swift

Failing in Swift Incremental RA - macOS - Apple Silicon

https://ci.swift.org/job/oss-swift-incremental-RA-macos-apple-silicon/2266/

```
[ RUN      ] CustomRRABI.retain
stderr>>> CRASHED: SIGSEGV
the test crashed unexpectedly
[     FAIL ] CustomRRABI.retain
CustomRRABI: Some tests failed, aborting
UXPASS: []
FAIL: ["retain"]
SKIP: []
To debug, run:
$ /Users/ec2-user/jenkins/workspace/oss-swift-incremental-RA-macos-apple-silicon/build/buildbot_incremental/swift-macosx-arm64/test-macosx-arm64/Runtime/Output/custom_rr_abi.swift.tmp/a.out --stdlib-unittest-in-process --stdlib-unittest-filter "retain"
```

rdar://102912772

Author: etcwilde

test/Runtime/custom_rr_abi.swift

@@ -6,6 +6,8 @@
 // UNSUPPORTED: use_os_stdlib
 // UNSUPPORTED: back_deployment_runtime
 
+// REQUIRES: rdar102912772
+
 import StdlibUnittest
 
 // A class that can provider a retainable pointer and determine whether it's