Multiple Update of blog post leads to doubled tags

[linkdotnet]

Happens with SqlServer

Steps to reproduce

• Open the blog and navigate to a blog post in admin mode (or create one and navigate afterwards)
• Edit the blog post and change the tags
• Save the blog post
• Edit the blog post again
• Check the tags in the overview page. They are doubled now

Possible Root cause

• CachedRepository does give a wrong version when editing the second time