Resolve logging verbosity issue in dask umap doctest

[vyasr]

As part of #6162 I was able to get all of the logging infrastructure in cuml transferred over to the new rapids-logger. This was more challenging in cuml than in some other repos because of the fact that cuml's log levels are inverted relative to spdlog's, and with this change I had to rework cuml's Python internals to do some translation (with a ton of help from @wphicks). With this translation we should have seen no changes to public APIs, but we were unable to diagnose one particular case in the dask UMAP code. To get #6162 merge I went ahead and updated the docstring to manually turn off verbosity, but somewhere in there something is going wrong so ideally we will want to get that resolved before the release.