test: improve test coverage; reorder theme-common files

[Josh-Cena]

Motivation

Discovered that a lot of un-covered files are because of our test coverage patterns... This commit bumps the test coverage to 86.53% functions 🎉

In addition, the theme-common files are getting messy. I reorganized them as components/hooks/contexts/utils.

Have you read the Contributing Guidelines on pull requests?

Yes

[netlify]

✅ [V2]

🔨 Explore the source changes: ff60ab9

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[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟠 Performance	58
🟢 Accessibility	100
🟢 Best practices	92
🟢 SEO	100
🟢 PWA	90

Lighthouse ran on https://deploy-preview-6956--docusaurus-2.netlify.app/

[github-actions]

Size Change: -71 B (0%)

Total Size: 805 kB

Filename	Size	Change
website/build/assets/js/main.********.js	612 kB	-71 B (0%)

ℹ️ View Unchanged

Filename	Size
website/.docusaurus/globalData.json	49.9 kB
website/build/assets/css/styles.********.css	105 kB
website/build/index.html	38.8 kB

_{compressed-size-action}

[slorber]

I reorganized them as components/hooks/contexts/utils.

🤷‍♂️ this may not scale so well to group files by type

as long as the public API is the same I don't care too much about the current organization, so ok to give this a try

[Josh-Cena]

Those "contexts" that I extracted are pretty apparent as standalone contexts (one consumer + one provider). Grouping everything under utils is, let's just say, confusing. Let's hope this helps us split the files in a more manageable fashion.