Add fixUser integration test

[prateek105]

Add unit test that covers the following mutation:

             === Mutant ID: 33 [DeleteExpressionMutation] ===

--- original
+++ mutant
@@ -98,7 +98,8 @@
 
         /// @dev zero balance
         accountBorrows[user].principal = 0;
-        accountBorrows[user].interestIndex = borrowIndex;
+        /// DeleteExpressionMutation(`accountBorrows[user].interestIndex = borrowIndex` |==> `assert(true)`) of: `accountBorrows[user].interestIndex = borrowIndex;`
+        assert(true);
 
         /// @dev current amount for a user that we'll transfer to the liquidator
         uint256 liquidated = accountTokens[user];

Path: mutants/33/src/MErc20DelegateFixer.sol

[ElliotFriedman]

nice one!

[ElliotFriedman]

LGTM!