fix(Card): Prevent other links than the Card Link from stretching

[VincentSmedinga]

Describe the pull request

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What

It lets only the Card Link stretch to cover the entire Card; not arbitrary other links.

Why

Other links would make the Card difficult to use.

How

• Replace two instances of the type selector with a class selector
• Group link styles for clarity and to prevent descending specificity
• Clarify comments and prevent them from being output in the build

Checklist

Before submitting your pull request, please ensure you have done the following. Check each checkmark if you have done so or if it wasn't necessary:

• Add or update unit tests
• Add or update documentation
• Add or update stories
• Add or update exports in index.* files
• Start the PR title with a Conventional Commit prefix, as explained here.

Additional notes

• n/a