introduce reentrancy guard

[predy-dev]

• introduce ReentrancyGuard to AMM contract
• mint after receive collateral at deposit function

[codecov]

Codecov Report

Merging #1 (dda631d) into main (3e9750b) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##             main       #1   +/-   ##
=======================================
  Coverage   97.45%   97.45%           
=======================================
  Files          20       20           
  Lines        1413     1413           
  Branches      215      215           
=======================================
  Hits         1377     1377           
  Misses         36       36           

Impacted Files	Coverage Δ
contracts/AMM.sol	92.95% <100.00%> (ø)

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