[ecash-lib] CI improvements for typescript projects

Summary:
Add support for running ecash-lib unit tests and building ecash-lib to CI

Since token-server is also a typescript project, add the introduced "test build" support there as well

Test Plan:
./contrib/teamcity/build-configurations.py ecash-lib-tests
./contrib/teamcity/build-configurations.py token-server-tests

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D15932