Improvements to reduce repainting

[charlesh88]

Closes #5247. Test instructions not yet included in the #5247 - will update there after we determine the best way to actually test these changes.

Describe your changes:

• Removes a CSS filter hover effect that seemed to cause a lot of repaints; replaced with a box-shadow effect in buttons and simple background color changes in other elements.
• Changes usage of transition: all to use specific properties instead via new mixin transition.
• Convert __pane-main to use absolute positioning to isolate object view and Time Conductor from page reflowing.

All Submissions:

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same update/change?
• Is this change backwards compatible? For example, developers won't need to change how they are calling the API or how they've extended core plugins such as Tables or Plots.

Author Checklist

• Changes address original issue?
• Tests included and/or updated with changes? N/A no functional changes.
• Command line build passes?
• Has this been smoke tested?
• Testing instructions included in associated issue OR is this a dependency/testcase change?

Reviewer Checklist

• Changes appear to address issue?
• Reviewer has tested changes by following the provided instructions?
• Changes appear not to be breaking changes?
• Appropriate automated tests included?
• Code style and in-line documentation are appropriate?
• Has associated issue been labelled unverified? (only applicable if this PR closes the issue)
• Has associated issue been labelled bug? (only applicable if this PR is for a bug fix)

[codecov]

Codecov Report

Merging #5876 (83ff0dc) into master (8831b75) will decrease coverage by 0.79%.
The diff coverage is n/a.

❗ Current head 83ff0dc differs from pull request most recent head b1c373f. Consider uploading reports for the commit b1c373f to get more accurate results

@@            Coverage Diff             @@
##           master    #5876      +/-   ##
==========================================
- Coverage   54.81%   54.03%   -0.79%     
==========================================
  Files         626      626              
  Lines       26630    26630              
  Branches     2405     2405              
==========================================
- Hits        14598    14390     -208     
- Misses      11370    11577     +207     
- Partials      662      663       +1     

Flag	Coverage Δ		*Carryforward flag
e2e-ci	39.35% <ø> (ø)		Carriedforward from 8831b75
e2e-full	51.08% <ø> (ø)		Carriedforward from 8831b75
e2e-stable	50.65% <ø> (-4.77%)	⬇️
unit	49.18% <ø> (+0.02%)	⬆️

*This pull request uses carry forward flags. Click here to find out more.

see 32 files with indirect coverage changes

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[michaelrogers]

These changes look good to me!

[akhenry]

@michaelrogers to address any broken tests and merge.

[davetsay]

@michaelrogers to fix tests and merge

[ozyx]

From the failed e2e tests traces, it looks like the "Edit & Save" button is disappeared?

[unlikelyzero]

This one needs some additional work. We should move it back into draft

[michaelrogers]

Resolved Failing Tests

• Browse bar hidden due to absolute positioning: resolved by position:relative and adding an toolbar height to top while in edit mode
• Collapsed inspector that was blocking the save button visibility
• Autoscale test: appears to be failing due to orange border applied to overlay plot