[nfc][memprof] Add missing license to MemProfTest (#91695)

Author: mtrofin

llvm/unittests/ProfileData/MemProfTest.cpp

@@ -1,3 +1,11 @@
+//===- unittests/Support/MemProfTest.cpp ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
 #include "llvm/ProfileData/MemProf.h"
 #include "llvm/ADT/DenseMap.h"
 #include "llvm/ADT/MapVector.h"