Align with octopus package in spack 2022 09 21

[fangohr]

As the spack folks have run black (https://github.com/spack/spack/commit/f52f6e99dbf1131886a80112b8c79dfc414afb7c) over their whole repository (a good idea in principle) two months ago, our version of octopus/package.py and theirs have diverged.

This pull request is meant to bring the changes back.

We have two commits:

• run black on our file (i.e. no change to behaviour of file)
• copy the file from [1] onto our file here.

From the diff of the second commit, we can see that again there are only re-formatting changes taking place with the exception of this one:

-from spack import *
+from spack.package import *

In any case, I think it will be essential to base our future merge requests to spack upstream on exactly the octopus/package.py file that is in upstream.

[1] https://github.com/spack/spack/blob/develop/var/spack/repos/builtin/packages/octopus/package.py

[fangohr]

Thanks to @iamashwin99 for offline review.