example showing difficulties in mocking modules with esm loader
the master branch is the baseline. running npm run test works as expected.
the first iteration is the branch esm-module. The test breaks because of esm issues within tap.
The internet suggests that this will be resolved in the next tap version, v15. For now the --no-esm parameter should help.
So the second intertion here is branch no-esm. While --no-esm fixes our previous issue, we get a new one: 
Apparently sinon cannot mock dependencies in esm modules, because esm imports are immutable. Again, the internet has suggestions to help: try a link seam. rewiremock is one link-seam capable mock loader so let's try in branch rewiremock
Unfortunately rewiremock won't load though
