Docs: Fix broken link to developer resources in README.md. (#29795)

[lephleg]

Description

A suggested fix for #29795.

How has this been tested?

Tested locally.

Types of changes

Documenation fix (non-breaking change which fixes an issue)

Checklist:

• My code is tested.
• My code follows the WordPress code style.
• My code follows the accessibility standards.
• I've tested my changes with keyboard and screen readers.
• My code has proper inline documentation.
• I've included developer documentation if appropriate.
• I've updated all React Native files affected by any refactorings/renamings in this PR.

[github-actions]

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[lephleg]

There's something wrong with the CI/CD process of the wp-env. I see it all over the place in the PRs submitted recently.

More info in #29797.

Edit: CI fixed.

[lephleg]

@jasmussen this looks like stagnant.. Could you take a look?
Same with #29699.

[jasmussen]

👌

Solid! Thank you so much.