Remove version pins on documentation dependencies

[wshanks]

Some of the pinned versions have gotten old and are confusing pip's resolver as it tries to find versions of the unpinned dependencies which are compatible with the pinned dependencies. The issues that led to the versions being pinned should be resolved.

[wshanks]

I organized the dependencies so it is easier to check for things. The obscures somewhat what pins were removed. The removed ones were:

jupyter-client, ipython, ipykernel -- all removed entirely since they were just pinned because new releases broke packages we actually depended on.

sphinx, qiskit-sphinx-theme -- removed the upper bound on these dependencies.

There are still bounds on black and pylint which we might remove or raise later.

[coruscating]

The built docs still look good after removing the pins. Thanks for organizing the file!