connection.h in duckdb-0.0.10

- old
+ new

@@ -5,11 +5,9 @@
     duckdb_connection con;
 };
 
 typedef struct _rubyDuckDBConnection rubyDuckDBConnection;
 
-VALUE cDuckDBConnection;
-
 void init_duckdb_connection(void);
 VALUE create_connection(VALUE oDuckDBDatabase);
 
 #endif