add cfg for test

src/lib.rs

@@ -871,10 +871,15 @@ impl InnerConnection {
 }
 
 impl Drop for InnerConnection {
+    #[cfg(not(test))]
     #[allow(unused_must_use)]
     fn drop(&mut self) {
         self.close();
     }
+    #[cfg(test)]
+    fn drop(&mut self) {
+        self.close().expect("Error while closing SQLite connection");
+    }
 }
 
 /// Old name for `Statement`. `SqliteStatement` is deprecated.