Remove unneeded include.



git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@183959 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/examples/lookup/main.cpp b/examples/lookup/main.cpp
index fabb5cb..fbb9084 100644
--- a/examples/lookup/main.cpp
+++ b/examples/lookup/main.cpp
@@ -27,7 +27,6 @@
 #endif
 
 #include <string>
-#include <vector>
 
 using namespace lldb;