Test for issue with API Server path handling

[MichalCz]

What?

API Server accepts paths strictly as their ASCII representation and that was the intended way, but using + in the path breaks the route.

What should be happenning is that either:

• querystring unescape should be applied
• + char should be treated as a non-special case

Included

Why?

However this has no current impact, path handling should work consistently.

Running this test will show the issue:

$ yarn test:packages -s @scramjet/api-server

Review checks:

These aspects need to be checked by the reviewer:

• [ ] Verify and confirm operation (please post a screenshot)
• [ ] All STH tests pass
• [ ] All Scramjet Cloud Platform tests pass
• [ ] Documentation is updated or no changes

[alicja-gruzdz]

Will be merged when the test passes.