Fix typo

src/lib.rs

@@ -505,7 +505,7 @@ impl BenchmarkRepository
 					let new_tree = match self.repository.find_tree(new_tree_object_id)
 					{
 						Ok(value) => value,
-						Err(error) => panic!("could obtain tree: {}", error),
+						Err(error) => panic!("could not obtain tree: {}", error),
 					};
 
 					trace!("Created tree object “{}”", new_tree_object_id);