[test] silence api-digester false alarm

Author: glessard

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

@@ -152,6 +152,12 @@ Func UnsafeMutablePointer.moveUpdate(from:count:) is a new API without @availabl
 Func UnsafeMutableBufferPointer.initialize(from:) has mangled name changing from 'Swift.UnsafeMutableBufferPointer.initialize<A where A == A1.Element, A1: Swift.Sequence>(from: A1) -> (A1.Iterator, Swift.Int)' to 'Swift.UnsafeMutableBufferPointer.initialize<A where A == A1.Element, A1: Swift.Sequence>(from: A1) -> (unwritten: A1.Iterator, index: Swift.Int)'
 Func UnsafeMutableBufferPointer.initialize(from:) has return type change from (τ_1_0.Iterator, Swift.Int) to (unwritten: τ_1_0.Iterator, index: Swift.Int)
 
+// This hasn't actually been removed; it was renamed at the source level while
+// retaining its old mangled/silgen name. The old source-level name is preserved
+// as an @_alwaysEmitIntoClient function. The source break was accepted as part of se-0405.
+Constructor String.init(validatingCString:) is a new API without @available attribute
+Constructor String.init(validatingUTF8:) has been removed
+
 // These haven't actually been removed; they are simply marked unavailable.
 // This seems to be a false positive in the ABI checker. This is not an ABI
 // break because the symbols are still present.