Added 2 test cases where fork failed

[youweiliang]

Fork failed to produce the same rewards after applying the same action

[codecov-commenter]

Codecov Report

Merging #751 (f60c377) into development (dd66b2c) will increase coverage by 0.39%.
The diff coverage is n/a.

@@               Coverage Diff               @@
##           development     #751      +/-   ##
===============================================
+ Coverage        88.84%   89.24%   +0.39%     
===============================================
  Files              130      130              
  Lines             7864     7864              
===============================================
+ Hits              6987     7018      +31     
+ Misses             877      846      -31     

Impacted Files	Coverage Δ
compiler_gym/service/service_cache.py	89.47% <0.00%> (-2.64%)	⬇️
...loop_tool/service/loop_tool_compilation_session.py	87.83% <0.00%> (-2.03%)	⬇️
compiler_gym/envs/gcc/service/gcc_service.py	95.60% <0.00%> (-0.37%)	⬇️
compiler_gym/service/connection.py	80.93% <0.00%> (+3.34%)	⬆️
compiler_gym/util/truncate.py	96.29% <0.00%> (+3.70%)	⬆️
compiler_gym/envs/llvm/datasets/poj104.py	75.67% <0.00%> (+33.78%)	⬆️

[ChrisCummins]

LGTM, thanks @youweiliang. Merging. I'll take a look at the specific problems to see if they can be fixed.

Cheers,
Chris