[CONTRACTS] DFCC loop assigns infererence with functions inlined

[qinheping]

Current loop assigns inference of DFCC can only infer targets considering only instructions in the same function. However, variables may be written to in the call of another function from function call inside the loop. So in this PR, we infer loop assigns based on a copy of the function and inlining all calls in the copy.

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[codecov]

Codecov Report

Attention: Patch coverage is 64.41718% with 58 lines in your changes missing coverage. Please review.

Project coverage is 78.75%. Comparing base (f2a7665) to head (45d7ad7).
Report is 2 commits behind head on develop.

Files with missing lines	Patch %	Lines
...ntracts/dynamic-frames/dfcc_infer_loop_assigns.cpp	68.31%	32 Missing ⚠️
src/goto-instrument/loop_utils.cpp	55.81%	19 Missing ⚠️
...trument/contracts/dynamic-frames/dfcc_cfg_info.cpp	63.15%	7 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #8490      +/-   ##
===========================================
- Coverage    78.88%   78.75%   -0.13%     
===========================================
  Files         1727     1727              
  Lines       198333   198768     +435     
  Branches     18475    18480       +5     
===========================================
+ Hits        156453   156549      +96     
- Misses       41880    42219     +339     

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