refactor: removes old workflows and LXD packages

[SecondSkoll]

No longer publishing this as an LXD-images package, LXD should have transitioned away by now
Removes old and non-functional workflows
Removes lxd-sphinx-extensions content
Changes author to me - I'm not bothered if this should be someone else, but Ruth is no longer here and I'm probably the most active TA in this repo...

[tang-mm]

There are still multiple projects using this old name in their requirements file. I'm afraid removing this transitional setup.py will cause their dependency install to fail, and they won't see the message that the package has been renamed.

Since the package is already marked as inactive on pypi, the maintenance effort left is minimal, I think they should be kept in place

[SecondSkoll]

There are still multiple projects using this old name in their requirements file. I'm afraid removing this transitional setup.py will cause their dependency install to fail, and they won't see the message that the package has been renamed.

Since the package is already marked as inactive on pypi, the maintenance effort left is minimal, I think they should be kept in place

0.0.16 is on pypi and is just an empty package that installs canonical-sphinx-extensions. There's no maintenance needed for this package, and even if we wanted to release a new version we can't - as we don't have creds for it on pypi.

Should workflows break from repos using this old package, they can see on pypi that it's been renamed. The setup file is contained in the package, so there's no need for it to be retained - and on the off chance it is there's the Git history.

[tang-mm]

Got your point about the published package! so +1

[SecondSkoll]

Sorry if I overexplain things :)