CONTRACTS: re-enable side effect checking in assigns/frees clauses (HOTFIX)

[remi-delmas-3000]

This PR re-enables side effect checking in functions called from assigns and frees clauses that was mistakenly disabled by #7671, and adds a new test that checks that side effect checking is actually performed.

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[qinheping]

Thank you!
Does the error message say it is caused by side-effect assign/free clause? I couldn't tell from test.desc.

[codecov]

Codecov Report

Patch coverage: 100.00% and no project coverage change.

Comparison is base (fa60087) 78.51% compared to head (445527d) 78.51%.

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #7699   +/-   ##
========================================
  Coverage    78.51%   78.51%           
========================================
  Files         1674     1674           
  Lines       191940   191946    +6     
========================================
+ Hits        150709   150715    +6     
  Misses       41231    41231           

Impacted Files	Coverage Δ
...t/contracts/dynamic-frames/dfcc_spec_functions.cpp	91.81% <100.00%> (+0.29%)	⬆️

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[feliperodri]

You don't need this include.