Make sure we remove the right patch from the image viewer when removing the slit overlay

[astrofrog]

Description

While testing out #762 I ran across a bug which was that the code to remove the slit overlay was assuming things about the order and number of marks in the figure, which caused an error of the type x not in list. This PR should fix it by making sure we remove the right mark.

Checklist for package maintainer(s)

This checklist is meant to remind the package maintainer(s) who will review this pull request of some common things to look for. This list is not exhaustive.

• Are two approvals required? Branch protection rule does not check for the second approval. If a second approval is not necessary, please apply the trivial label.
• Do the proposed changes actually accomplish desired goals? Also manually run the affected example notebooks, if necessary.
• Do the proposed changes follow the STScI Style Guides?
• Are tests added/updated as required? If so, do they follow the STScI Style Guides?
• Are docs added/updated as required? If so, do they follow the STScI Style Guides?
• Did the CI pass? If not, are the failures related?
• Is a change log needed? If yes, is it added to CHANGES.rst?
• Is a milestone set? Milestone is only currently required for PRs related to Imviz MVP.
• After merge, any internal documentations need updating (e.g., JIRA, Innerspace)?

[codecov]

Codecov Report

Merging #803 (1d0e35b) into main (4018090) will decrease coverage by 0.08%.
The diff coverage is 25.00%.

@@            Coverage Diff             @@
##             main     #803      +/-   ##
==========================================
- Coverage   67.21%   67.12%   -0.09%     
==========================================
  Files          65       65              
  Lines        4612     4618       +6     
==========================================
  Hits         3100     3100              
- Misses       1512     1518       +6     

Impacted Files	Coverage Δ
...onfigs/mosviz/plugins/slit_overlay/slit_overlay.py	51.35% <25.00%> (-4.54%)	⬇️

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[pllim]

Hmm... @rosteen and @javerbukh should have a look given they are attempting these PRs that sound related:

• Add slit overlay tests #769
• Mosviz zoom to slit or object #779

[rosteen]

As far as I can tell this breaks the slit overlay plugin. Unchecking the Visible box no longer removes the slit from the image, although if I uncheck it and then click another row then the new image won't have the slit displayed.

[astrofrog]

I'll investigate!

[astrofrog]

@rosteen - could you try again?

[rosteen]

Looks like the bug I was seeing is fixed, I can toggle slit visibility from the plugin again. Green checks on codecov would be nice, but I'm approving.

[pllim]

If this works now and unblocks the rest of the PRs, I think we should just merge. 😉

[rosteen]

That sounded like a second approval to me XD