AST: Use a builtin conformance for unconditional Copyable/Escapable

This generalizes what we were already doing for classes.

test/Distributed/distributed_incomplete_system_no_crash.swift

@@ -1,8 +1,6 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-swift-frontend -typecheck -verify -disable-availability-checking 2>&1 %s
 
-// XFAIL: noncopyable_generics
-
 // REQUIRES: concurrency
 // REQUIRES: distributed
 
@@ -50,4 +48,4 @@ public final class CompletelyHollowActorSystem_NotEvenTypes: DistributedActorSys
   // expected-error@-3{{class 'CompletelyHollowActorSystem_NotEvenTypes' is missing witness for protocol requirement 'remoteCall'}}
   // expected-note@-4{{add stubs for conformance}}
   // expected-note@-5{{add stubs for conformance}}
-}
+}