message: Fix typo in describing ensure_len function
diff: @@ -834,7 +834,7 @@ fn extend_lower_triangular_matrix<T: Default>(
  new_node_capacity + 1
  }
  -/// Grow a Vec by appending the type's default value the `size` is reached.
  +/// Grow a Vec by appending the type's default value until the `size` is reached.
  fn ensure_len<T: Default>(v: &mut Vec<T>, size: usize) {
  if let Some(n) = size.checked_sub(v.len()) {
  v.reserve(n);
  