These keep on taking just longer than 30s on my local machine when run
in parallel with the rest of the tests (i.e. with `ninja test`). Testing
them individually, they do terminate correctly.
Signed-off-by: Philip Withnall <withnall@endlessm.com>
Meson has the ability to classify tests according to "suites", a list of
tags. This is especially useful when we want to run specific sets of
tests — e.g. only GLib's tests — instead of the whole test suite. It
also allows us to classify special tests, like "slow" ones, so that we
can only run them when needed.
