The app we run headless tests on (headless-test/examples/todoApp) is a copy of waspc/examples/todoApp that diverged over time.

Having multiple copies of "apps for testing" is a maintenance burden. We should combine these two apps into a single app under waspc/examples/todoApp and run the tests on that one.

Related #1976
Related #2011
See this when implementing: #2044 (comment)