Upgrade Typescript to latest version in Ts-Mocha

[huytr1995]

Hi we are currently using ts-mocha for unit test but lately when we trying to pull in react-pdf beta version, we can't run our test in Github CI because ts-mocha is using an old version of typescript which is 3.3 while our project is using 4.3 and pdf.js is using 4.7. Is there any chance u can upgrade you project with the latest typescript version

[piotrwitek]

Hey, ts-mocha is not using any specific version, it's using the version installed in the workspace, so it's using v4.3 in your case. So could you tell me what is the problem causing ts-mocha not working with v4.3? as I don't see any breaking changes that would make the source code not compatible.