integrationservertest: Adding meta-tests

[ericywl]

Currently, the tests themselves don't have any tests (henceforth called meta-tests to avoid confusion). If we make some mistakes in the tests, the tests could potentially pass even though it is wrong (false positive).

Investigate adding meta-tests so that we can be sure that future changes won't introduce false positives.

[endorama]

@ericywl what's your idea of the scope of this task? What are the sources that could lead to false positives?