Test pact-gen-ts using multiple TypeScript versions

[pawfa]

TypeScript compiler changes have a huge impact on pact-gen-ts functionality. Due to TS not following semantic versioning it is hard to predict when it might cause issues with pact-gen-ts library.

My suggestion is to test library with different versions of TypeScript - including @next. Example implementation provided here: react-redux gh action with different TS versions.

It could give us quick feedback whether the API changed in upcomfing TypeScript version

[pawfa]

Closing issue after coming to a conclusion that this will not make maintenance easier. Having the knowledge in advance that pact-gen-ts will not work with new TypeScript version will not allow to react and fix the issue sooner. It is because most of the fixes require ts-morph update so we still have to wait for it and only after that, pact-gen-ts can be aligned with news TS version.