Merge pull request swiftlang#40135 from lorentey/fix-KVOKeyPath-backdeployment

[test] Adjust KVOKeyPaths test for back deployment

Author: lorentey

test/stdlib/KVOKeyPaths.swift

@@ -215,6 +215,6 @@ testObjectForOptionalKeyPath.optionalObject = nil
 testObjectForOptionalKeyPath.optionalObject = "foo"
 
 // CHECK-51-LABEL: observe keyPath with optional value
-// CHECK-51-NEXT: oldValue = Optional(nil), newValue = {{Optional\(nil\)|nil}}
-// CHECK-51-NEXT: oldValue = Optional(nil), newValue = {{Optional\(nil\)|nil}}
-// CHECK-51-NEXT: oldValue = Optional(nil), newValue = Optional(Optional("foo"))
+// CHECK-51-NEXT: oldValue = {{Optional\(nil\)|nil}}, newValue = {{Optional\(nil\)|nil}}
+// CHECK-51-NEXT: oldValue = {{Optional\(nil\)|nil}}, newValue = {{Optional\(nil\)|nil}}
+// CHECK-51-NEXT: oldValue = {{Optional\(nil\)|nil}}, newValue = Optional(Optional("foo"))