Remove duplicate include

Must have been a mismerge at some point.

Change-Id: I7132f85649697484cb3a5537a5b2adbc4ed5e8ce
Reviewed-on: https://boringssl-review.googlesource.com/c/boringssl/+/90127
Commit-Queue: David Benjamin <davidben@google.com>
Auto-Submit: David Benjamin <davidben@google.com>
Reviewed-by: Lily Chen <chlily@google.com>
Commit-Queue: Lily Chen <chlily@google.com>

ssl/handshake_server.cc

diff --git a/ssl/handshake_server.cc b/ssl/handshake_server.cc
index f7fea02..3e85edf 100644
--- a/ssl/handshake_server.cc
+++ b/ssl/handshake_server.cc
@@ -37,7 +37,6 @@
 
 #include "../crypto/bytestring/internal.h"
 #include "../crypto/internal.h"
-#include "../crypto/bytestring/internal.h"
 #include "internal.h"