Make going_to variable cprover-prefixed

[qinheping]

The goint_go variables are cprover variables and hence should be cprover-prefixed.

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.29%. Comparing base (52c3dbb) to head (f993f8c).

Additional details and impacted files

@@           Coverage Diff            @@
##           develop    #8312   +/-   ##
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  Coverage    78.29%   78.29%           
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  Files         1722     1722           
  Lines       188448   188448           
  Branches     18464    18452   -12     
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  Hits        147540   147540           
  Misses       40908    40908           

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[tautschnig]

Please also update src/goto-instrument/contracts/dynamic-frames/dfcc_is_cprover_symbol.cpp

[martin-cs]

Should it also go into linking/remove_internal_symbols.cpp ? More generally, what is the procedure for adding a CPROVER_PREFIX symbol? Do we have a list anywhere of all of them like goto-programs/system_library_symbols.cpp?