tests: Remove duplicate included header file in src/test/test.c.

 * FIXES #25271: https://bugs.torproject.org/25271

src/test/test.c

@@ -62,7 +62,6 @@ double fabs(double x);
 #include "routerparse.h"
 #include "statefile.h"
 #include "crypto_curve25519.h"
-#include "onion_ntor.h"
 
 /** Run unit tests for the onion handshake code. */
 static void