Upgraded Q -> M from #164 [1674419095024]

Judge has assessed an item in Issue 164 as M risk. The relevant finding follows: LOW‑1 The Contract Should approve0 First Some tokens like USDT L199 do not work when changing the allowance from an existing non-zero allowance value. They must first be approved by zero and then the actual allowance...

The Contract Should approve(0) first

Originally submitted by warden defsec in 198, duplicate of 178 related to the use of safeApprove. This is upgraded from a QA report to standalone issue because it correctly described the revert when trying to call safeApprove on non-zero allowance. QA report that only describe safeApprove as...