Dashboard: Bug fixes for color panel translation and detail template capitalization

[BrittanyIRL]

Summary

Two small bug fixes to improve internationalization.

1. Giving the color dropdown that shows [color 1] + n a true plural option for if translations need it.
2. Moving the forced capitalization of a button on the detail template view to css.

Relevant Technical Choices

• using _n not __ for plural of numbers in i18n

To-do

N/A

User-facing changes

• None, should appear the exact same to the user
  (Areas to regression test are the color filter on templates and the 'USE TEMPLATE' button on the detail template view)

Testing Instructions

• Regression test that the color label updates the same on the template color picker
• and that the 'USE TEMPLATE' button on the detail view of template is still all caps.

---

Addresses #2293

[codecov]

Codecov Report

Merging #2311 into master will increase coverage by 0.00%.
The diff coverage is 100.00%.

@@            Coverage Diff            @@
##             master    #2311   +/-   ##
=========================================
  Coverage     66.12%   66.13%           
  Complexity      314      314           
=========================================
  Files           651      651           
  Lines         10735    10736    +1     
=========================================
+ Hits           7099     7100    +1     
  Misses         3636     3636           

Impacted Files	Coverage Δ	Complexity Δ
assets/src/dashboard/components/dropdown/index.js	86.53% <ø> (ø)	0.00 <0.00> (ø)
...s/src/dashboard/components/templateNavBar/index.js	100.00% <100.00%> (ø)	0.00 <0.00> (ø)

[github-actions]

Size Change: +33 B (0%)

Total Size: 829 kB

Filename	Size	Change
assets/js/stories-dashboard.js	441 kB	+33 B (0%)

ℹ️ View Unchanged

Filename	Size	Change
assets/css/edit-story.css	269 B	0 B
assets/css/stories-dashboard.css	305 B	0 B
assets/css/web-stories-embed-block.css	501 B	0 B
assets/js/edit-story.js	371 kB	0 B
assets/js/web-stories-embed-block.js	15.7 kB	0 B

_{compressed-size-action}

[swissspidy]

Thanks a lot 🎉 👍