[doc] tag list extension tutorial

[jcalcaben]

Description

Replaces the old tag list component tutorial with a tag list extension tutorial using more up to date patterns with Targets and Targetables.

Related Issue

Closes #3020

Closes PWA-1470

Acceptance

Any internal developer

Verification Stakeholders

Any internal developer

@larsroettig (optional)

Specification

Verification Steps

1. Navigate to the pwa-devdocs directory: cd pwa-devdocs
2. Run the HTML preview server: yarn develop
3. Verify build succeeds and loads preview site
4. Navigate to /tutorials/extension-development/taglist/
5. Verify page loads and content is accurate
6. Verify CodeSandbox iframe at the end of the topic loads successfully
7. Verify topic is listed on the left navigation
8. Verify Create a TagList component is NOT listed on the left navigation

Screenshots / Screen Captures (if appropriate)

Checklist

• I have added tests to cover my changes, if necessary.
• I have added translations for new strings, if necessary.
• I have updated the documentation accordingly, if necessary.

[PWAStudioBot]

	Messages
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Generated by 🚫 dangerJS against 1c0f706

[supernova-at]

Looks great! One minor change request but approved either way 👍