Resolve "Follow-up from "Adding dnest4 Sampler""

Requires !888 (merged) Closes #533 (closed)

bilby/core/sampler/base_sampler.py

@@ -609,7 +609,7 @@ class NestedSampler(Sampler):
         """
         If using a temporary directory, the output directory is moved to the
         temporary directory.
-        Used for Dnest4 and Pymultinest.
+        Used for Dnest4, Pymultinest, and Ultranest.
         """
         if self.use_temporary_directory:
             temporary_outputfiles_basename = tempfile.TemporaryDirectory().name