Cleanup codebase

[adamjtaylor]

From the legacy htan-artist repo there are a number of half-developed or unused features in the codebase.

This PR removes these to allow our main branch to only include used and functional features.

[thomasyu888]

Nice! I'll let rixing do another review, but this looks great.

[rxu17]

I had a couple comments.

If any of the unused features plan to be included as part of this ticket, might be worthwhile moving them into a TODO README or leaving them there but adding TODO comments, thoughts?

[rxu17]

Similar comments as the above. They are referenced here.

[adamjtaylor]

@rxu17 @tom Thanks for looking over. I've made a number of further changes.
Notably

• Uses current release of Minerva (and avoids the need for two versions to be maintained)
• Test datasets are tidied up with one example for H&E and one example for Multiplexed images.
• For H&E which takes a fixed minerva story, this is added in the workflow rather than requiring a separate process to be launched just for a cp to occur
• Processes are tagged with the ID which helps with debugging in Tower
• All processes have labels for resource allocation (resource allocation is currently overkill so should optimise in a future PR)

I've been using these features (in the ajt_develop branch) for HTAN's release 4 and have had no obvious issues