Eclipse Foundation 404 error page has outdated content

Summary

Various Eclipse Foundation 404 error pages contains outdated links.

Steps to reproduce

For eclipse.dev:

• Go to some non-existing URL, like https://eclipse.dev/does_not_exist.
• It redirects to https://www.eclipse.org/errors/404.html.
• This 404 error page seems to be outdated. For instance, the link to 'Webmaster FAQ' points to https://wiki.eclipse.org/wiki_action_404.html that itself now gives a similar 404 error, but no Webmaster FAQ.

For eclipse.org:

• Go to https://www.eclipse.org/doesn'texist.
• It shows a different 404 page, but also a link to the 'webmaster FAQ' that doesn't work.

For wiki.eclipse.org:

• Go to https://wiki.eclipse.org and click on the 'History' tab. It goes to https://wiki.eclipse.org/index.php?title=Main_Page&action=history, which gives a 404. It has a similar broken link to Webmaster FAQ.

Maybe other Eclipse Foundation domains have the same problem.