fix: replace markdown mailto link with html

[ctorgalson]

What does this change?

This PR changes the markdown mailto link on the markdown page used to create the For Developers documentation page to an HTML link because the markdown link gets transformed into <a href="hello@localgovdrupal.org">hello@localgovdrupal.org</a> (which gets interpreted as a relative link to a html document).

It's possible changing it to hello@localgovdrupal.org would also work, as Github manages to convert that to a correct mailto link in this sentence.

How to test

How can we measure success?

1. click the hello@localgovdrupal.org link on the live version of the page: the browser navigates to https://docs.localgovdrupal.org/devs/hello@localgovdrupal.org
2. click on the hello@localgovdrupal.org link on the html generated by the changed markdown: it behaves as a mailto link

Have we considered potential risks?

n/a

Images

n/a

Accessibility

n/a

[netlify[bot]]

✅ Deploy Preview for inspiring-euclid-d918c8 ready!

Name	Link
🔨 Latest commit	3c6458694250ae984ca89f4abe4d4bc8423d6714
🔍 Latest deploy log	https://app.netlify.com/sites/inspiring-euclid-d918c8/deploys/66c4b8f927e29a000994198b
😎 Deploy Preview	https://deploy-preview-272--inspiring-euclid-d918c8.netlify.app
📱 Preview on mobile	Toggle QR Code... Use your smartphone camera to open QR code link.

---

To edit notification comments on pull requests, go to your Netlify site configuration.

[ctorgalson]

I should have noted time provided by Annertech :)