Require PyOpenCL context for HI of LazyEBSD

[hakonanes]

Description of the change

This PR should fix #614 by requiring PyOpenCL and a compatible driver context to be available when trying to perform Hough indexing of a Dask array with PyEBSDIndex. By doing this check early, we ensure that PyEBSDIndex can use PyOpenCL and that it will not fall back to its CPU implementation, which then calls Numba and errors.

Will make a v0.8.1 release as soon as this PR is merged.

Progress of the PR

• Docstrings for all functions
• Unit tests with pytest for all lines
• Clean code style by running black via pre-commit
• Re-run notebooks using Hough indexing (because print message changed, "GPU" -> "PyOpenCL")
• Update changelog release date

Minimal example of the bug fix or new feature

Error message that should be raised when PyOpenCL is installed but no compatible driver is available (error message copy/pasted):

>>> import pyopencl as cl
>>> cl.get_platforms()
[]
>>> import kikuchipy as kp
>>> s = kp.data.nickel_ebsd_small()
>>> s.hough_indexing(None, None)
UserWarning("Hough indexing of lazy signals must use PyOpenCL and a compatible driver. 
    See https://documen.tician.de/pyopencl/misc.html for details")

For reviewers

• The PR title is short, concise, and will make sense 1 year later.
• New functions are imported in corresponding __init__.py.
• New features, API changes, and deprecations are mentioned in the unreleased
  section in CHANGELOG.rst.
• New contributors are added to release.py, .zenodo.json and
  .all-contributorsrc with the table regenerated.

[hakonanes]

@ericpre: I would be very greatful if you could give your opinion on whether the following fixes #614:

https://github.com/pyxem/kikuchipy/pull/615/files#diff-3bd901a3b67244c36540d9734e61606033674b7e3ee2d92761ac14d6a6937aebR45-R58

Relevant part of PyEBSDIndex' PyOpenCL context setup: https://github.com/USNavalResearchLaboratory/PyEBSDIndex/blob/main/pyebsdindex/opencl/openclparam.py#L67.

[ericpre]

@ericpre: I would be very greatful if you could give your opinion on whether the following fixes #614

I have left some comments but I don't have more time than this. One way to check is to push a branch of the https://github.com/hyperspy/hyperspy-extensions-list repo on github using this branch of kikuchipy and removing the corresponding tests being skipped.

[ericpre]

I would use pyopencl directly instead, because the return of clparams.get_context() could be regarded as an implementation details of pyebsdindex.
I would expect that pyopencl have a clean approach to do this.

[hakonanes]

Agreed. I've done this instead.

[ericpre]

Off the top of my head: using assert is intended for development and testing and is not a good pattern to catch runtime errors.

[hakonanes]

Thanks, I've replaced it with an if/else.

[hakonanes]

One way to check is to push a branch of the https://github.com/hyperspy/hyperspy-extensions-list repo on github

Thanks for the tip, the kikuchipy test suite passes in the "dev" runs when this PR's branch is used: https://github.com/hakonanes/hyperspy-extensions-list/actions/runs/4204973562/jobs/7296399979