fix(v2): specify proper TS path in classic theme

[lex111]

Motivation

Reported from Discord chat:

2.0.0-alpha.70 and 2.0.0-alpha.71 no longer output *.tsx files like the documentation says (https://v2.docusaurus.io/docs/typescript-support#swizzling-typescript-theme-components) when swizzling with the --typescript flag. They are *.js files instead. I looked through the release notes for said versions on whether support for this has been dropped but couldn't find anything. Did I miss anything? Is this supposed to happen?

Have you read the Contributing Guidelines on pull requests?

Yes

Test Plan

Try run yarn swizzle @docusaurus/theme-classic Footer --typescript

Related PRs

(If this PR adds or changes functionality, please take some time to update the docs at https://github.com/facebook/docusaurus, and link to your PR here.)

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Size Change: 0 B

Total Size: 564 kB

ℹ️ View Unchanged

Filename	Size	Change
website/build/assets/css/styles.********.css	87.3 kB	0 B
website/build/assets/js/main.********.js	390 kB	0 B
website/build/blog/2017/12/14/introducing-docusaurus/index.html	60.7 kB	0 B
website/build/docs/introduction/index.html	235 B	0 B
website/build/index.html	25.6 kB	0 B

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[github-actions]

⚡️ Lighthouse report for the changes in this PR:

Category	Score
🟢 Performance	92
🟢 Accessibility	96
🟢 Best practices	100
🟢 SEO	100
🟢 PWA	95

Lighthouse ran on https://deploy-preview-4381--docusaurus-2.netlify.app/classic/

[slorber]

good catch thanks :)