Bump kr8s to 0.14.2

[jacobtomlinson]

Closes #853

[jacobtomlinson]

I spent some time in #883 trying to figure out what change in kr8s was causing the CI deadlock.

It looks like the problem is because when we run the dask-kubernetes test suite both the controller and client code run within the same process, but on separate event loops. The client caching in kr8s meant that the same API client and other async objects was being shared between these loops, which caused the deadlock. Annoyingly this isn't a real world use case for dask-kubernetes and only happens in the test suite.

There was a fix in kr8s a while back which ensured that the client caching checked the current thread to ensure this doesn't happen, due to an assumption that different event loops must exist in different threads. However that seems to not be true in this case and both loops were reporting the same thread ID.

I tested out a fix that also take the event loop id into account directly from the kr8s PR in #883 and things seem to be passing. So I've made a v0.14.2 release of kr8s and updated this PR to point to the new release which hopefully gets things unblocked.