Test case fixes for isolated conformances

Author: DougGregor

test/IRGen/isolated_conformance.swift

@@ -2,6 +2,7 @@
 
 // REQUIRES: PTRSIZE=64
 // REQUIRES: concurrency
+// REQUIRES: swift_feature_IsolatedConformances
 // UNSUPPORTED: CPU=arm64e
 
 protocol P {
@@ -14,7 +15,7 @@ protocol P {
 // CHECK-SAME: ptr @"$s20isolated_conformance1XVyxGAA1PAAWP
 // CHECK-SAME: i32 524288
 // CHECK-SAME: @"symbolic ScM"
-// CHECK-SAME: ptr @"$sScMs11GlobalActorsMc"
+// CHECK-SAME: ptr @"got.$sScMs11GlobalActorsMc"
 @MainActor
 struct X<T>: isolated P {
   func f() { }

test/abi/Inputs/macOS/arm64/concurrency/baseline-asserts

@@ -997,6 +997,7 @@ _swift_task_getMainExecutor
 _swift_task_hasTaskGroupStatusRecord
 _swift_task_isCancelled
 _swift_task_isCurrentExecutor
+_swift_task_isCurrentGlobalActor
 _swift_task_isOnExecutor
 _swift_task_isOnExecutor_hook
 _swift_task_localValueGet