Marketplace: Replace external link with clickable span

[lsl]

This isn't a great fix but it gets rid of the console warning.

@SaxonF the card underneath this link is still clickable (we're nesting link <a /> tags in html and its giving a react error), should we just replace the whole card's link to the support doc or should we implement some kind of full overlay? At the moment we're rendering the link in the middle of the card to make space for it, imo we should do something different maybe make the card not clickable and only have the middle link or move the card link to the card title and have two.

Changes proposed in this Pull Request

• Replace ExternalLink with clickable span

Testing instructions

• Search for something that displays an incompatible plugin, e.g. seo http://calypso.localhost:3000/plugins/?s=seo
• Observe no nested <a /> warnings in the console.

Fixes #63586

[github-actions]

Calypso Live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-33978

Jetpack Cloud live (direct link)

https://calypso.live?image=registry.a8c.com/calypso/app:build-33978&env=jetpack

[matticbot]

Here is how your PR affects size of JS and CSS bundles shipped to the user's browser:

Sections (~24 bytes added 📈 [gzipped])

name         parsed_size           gzip_size
plugins           +109 B  (+0.0%)      +24 B  (+0.0%)
marketplace       +109 B  (+0.0%)      +24 B  (+0.0%)

Sections contain code specific for a given set of routes. Is downloaded and parsed only when a particular route is navigated to.

Legend

What is parsed and gzip size?

Parsed Size: Uncompressed size of the JS and CSS files. This much code needs to be parsed and stored in memory.
Gzip Size: Compressed size of the JS and CSS files. This much data needs to be downloaded over network.

Generated by performance advisor bot at iscalypsofastyet.com.

[paulopmt1]

Worked as expected. Good job @lsl!