Remove footgun function

consensus/types/src/runtime_var_list.rs

@@ -118,10 +118,6 @@ impl<T> RuntimeVariableList<T> {
         }
     }
 
-    pub fn set_max_len(&mut self, max_len: usize) {
-        self.max_len = Some(max_len);
-    }
-
     /// Returns the number of values presently in `self`.
     pub fn len(&self) -> usize {
         self.vec.len()