If the test has other dependencies they can also be listed in waiton,
so for example:

testA: waiton !end_of_tests
testB: waiton testA !end_of_tests

From a DAG perspective, it would look something like:

...---[!end_of_tests]--[testA]--[testB]

The "!end_of_tests" is effectively a "virtual" (not actual) test definition
that only Megatest knows about and always successfully runs.