Remove unclear comment.

BUILD

@@ -47,7 +47,6 @@ COPTS = select({
         "-Wno-sign-compare",
         "-Wno-unused-function",
         # Prevents ISO C++ const string assignment warnings for pyext sources.
-	# no-write-strings is the standard GCC flag as of at least v5.
         "-Wno-writable-strings",
         "-Wno-write-strings",
     ],