fix: FIT-248: Adapt scrollbars to dark mode

[carly-bartel]

Reason for change

Scrollbars on several pages in Dark Mode were appearing white, which was a regression as per Ricardo Cabral. This was due to some elements missing the styled-scrollbar mixin, preventing them from adopting the correct dark mode styling.

Screenshots

Before

After

Testing

The fix was verified by following the steps to reproduce the original bug:

1. As OWNER, log in to https://ls-release.appx.humansignal.com/
2. Click on Create project button
3. Observe that Create Project modal pops up
4. Navigate to data import tab
5. Import provided data: TSSyncData.json
6. Navigate to Labeling Interface tab
7. Click on Custom template option
8. Add provided config: AudioVideoTSSyncConfig.txt
9. Click on Save button
10. Observe that you’re at Data Manager
11. Click on imported task
12. Observe that you’re at Quick View
13. Confirm that several scrollbars are now adapted to Dark Mode.
14. Navigate to Settings > Labeling Interface page
15. Confirm that the horizontal scrollbar is now adapted to Dark Mode.
16. Navigate to Organization page
17. Confirm that the scrollbar on the right side is now adapted to Dark Mode.

Reviewer notes

The changes primarily involve removing the 'styled-scrollbar' mixin and applying them globally in the tailwind.css file

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 65.89%. Comparing base (b7fc7f7) to head (b676250).
Report is 4 commits behind head on develop.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #7985      +/-   ##
===========================================
+ Coverage    63.68%   65.89%   +2.21%     
===========================================
  Files          715      504     -211     
  Lines        50292    33376   -16916     
  Branches      8589     8589              
===========================================
- Hits         32027    21993   -10034     
+ Misses       18262    11380    -6882     
  Partials         3        3              

Flag	Coverage Δ
lsf-e2e	59.49% <ø> (?)
lsf-integration	55.60% <ø> (ø)
lsf-unit	9.40% <ø> (ø)
pytests	?

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[yyassi-heartex]

/fmt

Workflow run

[hlomzik]

Can we move this mixin to a dedicated file and import it? That would make it universal and easily accessible in any other places

[carly-bartel]

Can we move this mixin to a dedicated file and import it? That would make it universal and easily accessible in any other places

@hlomzik i removed all of the mixins and just applied the scrollbar style globally in the tailwind.css file