try to fix the api-digester test

Author: benpious

test/api-digester/stability-stdlib-abi-without-asserts.test

@@ -57,6 +57,7 @@ Func MutableCollection.moveSubranges(_:to:) has been removed
 Func MutableCollection.removeSubranges(_:) has been removed
 Func RangeReplaceableCollection.removeSubranges(_:) has been removed
 Struct AnyHashable has added a conformance to an existing protocol _HasCustomAnyHashableRepresentation
+Class AnyKeyPath has added a conformance to an existing protocol CustomDebugStringConvertible
 Struct DiscontiguousSlice has been removed
 Struct RangeSet has been removed
 Subscript Collection.subscript(_:) has been removed