incrementing sufficient accounts references with saturating_add for safety. (#2768)
Even though it is difficult to overflow the sufficients variable, since an attacker that is willing to rapidly increase the number must every time deposit a minimum deposit of a given asset, it is safer to use saturating_add(). --------- Co-authored-by: Bastian Köcher <[email protected]> Co-authored-by: joe petrowski <[email protected]>