Update footprint orientations on viewer rotation

[bmorris3]

When the Orientation plugin changes reference data to rotate a viewer, the footprint method that's currently used to update each of the footprints' properties tries to act on the selected overlay only, not all overlays.

This PR makes a separate method that gets triggered by changes in reference data, and explicitly calls the relevant method (_change_overlay) on each overlay.

Change log entry

• Is a change log needed? If yes, is it added to CHANGES.rst? If you want to avoid merge conflicts,
  list the proposed change log here for review and add to CHANGES.rst before merge. If no, maintainer
  should add a no-changelog-entry-needed label.

Checklist for package maintainer(s)

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• 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 milestone set? Set this to bugfix milestone if this is a bug fix and needs to be released ASAP; otherwise, set this to the next major release milestone. Bugfix milestone also needs an accompanying backport label.
• After merge, any internal documentations need updating (e.g., JIRA, Innerspace)?

[bmorris3]

I found some cases where the traitlet for PA was being interpreted as a string, which causes problems when a float PA offset is subtracted. Here I ensure we're only giving these properties as floats.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 88.77%. Comparing base (e0b1ec3) to head (fd3f2da).
Report is 149 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2918      +/-   ##
==========================================
+ Coverage   88.76%   88.77%   +0.01%     
==========================================
  Files         111      111              
  Lines       17178    17181       +3     
==========================================
+ Hits        15248    15253       +5     
+ Misses       1930     1928       -2     

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[camipacifici]

Works!! Thank you!!
As a follow up, can we have a spinner in the orientation plugin when it rotates to a new angle? It takes a little bit and the user might feel like clicking again.

[gibsongreen]

Love the small diff and I had thought a lot about how to write this test, took some time to go through it, fan of the creative logic, and everything looks good to me!