typo in github link for new version

[lcube45]

There is a small typo in the disclaimer for a new version. Links to preview tag and changelog lead to 404 page.

• Current link for tag 1.15.1 is : https://github.com/inetum-orleans/docker-devbox-ddb/releases/tag/1.15.1
• Correct link for tag 1.15.1 should be : https://github.com/inetum-orleans/docker-devbox-ddb/releases/tag/v1.15.1