Remove "const" from convertTSFunction()'s return type.

There's no particular reason to mark it as such. The other convert*
functions have no const either.

src/bin/pg_dump/pg_dump.c

@@ -225,7 +225,7 @@ static char *format_function_signature(Archive *fout,
 static char *convertRegProcReference(Archive *fout,
 						const char *proc);
 static char *convertOperatorReference(Archive *fout, const char *opr);
-static const char *convertTSFunction(Archive *fout, Oid funcOid);
+static char *convertTSFunction(Archive *fout, Oid funcOid);
 static Oid	findLastBuiltinOid_V71(Archive *fout, const char *);
 static Oid	findLastBuiltinOid_V70(Archive *fout);
 static void selectSourceSchema(Archive *fout, const char *schemaName);
@@ -11176,7 +11176,7 @@ convertOperatorReference(Archive *fout, const char *opr)
  * caller should ensure we are in the proper schema, because the results
  * are search path dependent!
  */
-static const char *
+static char *
 convertTSFunction(Archive *fout, Oid funcOid)
 {
 	char	   *result;