Deleting a repo and then recreating with the same name fails under some circumstances (BB-6363)

Attempting to create a new repository with the same name as a deleted repository will fail if there is an existing redirection URL or if the background process fails while deleting and leaves behind dead data.

Original text:

Initially I've created an hg repositury in error, my plan was to create git one. So, I deleted it and created a new one, with the same name but this time using git. Now, after the update this repository seems to be hg one again and is empty, and there are no files in it, if I browse it via site. But I can still clone and push to it via git command line, so it is there, but somehow I can't access it on site.