hnb-test.c: Remove pdus.h include as it is not used

The messages are constructed so no need to include the binary asn1 data.
diff --git a/src/tests/hnb-test.c b/src/tests/hnb-test.c
index cc5dfac..5908716 100644
--- a/src/tests/hnb-test.c
+++ b/src/tests/hnb-test.c
@@ -235,8 +235,6 @@
 	return rc;
 }
 
-#include "pdus.h"
-
 static void hnb_send_register_req(struct hnb_test *hnb_test)
 {
 	HNBRegisterRequest_t request_out;