Use non-unicode filepaths for Windows when updating mtime.

PiperOrigin-RevId: 707548791

common/remote_file_oss.cc

diff --git a/common/remote_file_oss.cc b/common/remote_file_oss.cc
index 23dd863..bcee354 100644
--- a/common/remote_file_oss.cc
+++ b/common/remote_file_oss.cc
@@ -253,8 +253,8 @@
   }
 
 #if defined(_MSC_VER)
-  HANDLE file = CreateFile(path.data(), GENERIC_READ, FILE_SHARE_READ, NULL,
-                           OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
+  HANDLE file = CreateFileA(path.data(), GENERIC_READ, FILE_SHARE_READ, NULL,
+                            OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL, NULL);
   if (file == INVALID_HANDLE_VALUE) {
     return absl::InternalError(absl::StrCat("Failed to open ", path, "."));
   }