Update overlinking URL in guide
Commit 29cddacd changed the hyperlink in the year 2014 already. Now, the link broke again. I found:
a) http://web.archive.org/web/20140523093421/http://wiki.mandriva.com:80/en/Overlinking
b) http://web.archive.org/web/20190921014607/https://wiki.openmandriva.org/en/Overlinking_issues_in_packaging
c) https://wiki.mageia.org/en/Overlinking_issues_in_packaging
Not sure, which one to take, otherwise I would have created a Merge Request. By the way, the current version online should be updated afterwards, at least Commit b51cd216 is not present there yet.