Add some new packages to the test images (!1089) · Merge requests · lscsoft / bilby

This MR adds some packages that we need for upcoming/recent changes the test images.

dill. I don't know why this is currently missing, but gets installed at the start of every test job.
skimage. This is needed for running the logo example that now runs on schedules.
celerite/george. These are required for !1086 (merged).
bilby-cython. Needed for !1053 (merged).

Add some new packages to the test images