Add functional test framework

[aureleoules]

This repo is missing a functional test framework to check that the mutators do not hit edge cases and parse correctly the AST.

Tips

• C++ files should be compiled with bear g++ file.cpp so that bear can generated a compile_commands.json necessary for clang-tidy.
• The shared library can be loaded with clang-tidy-16 --quiet -fix -load=$PWD/build/libbitcoin-mutator.so -checks='mutator-or-to-and' sample.cpp