The git repository creation allow to use hyphen and dot in the repository name.
But the reference regexp don't accept these two characters to recognize a reference to a repo.

Steps to reproduce:
1- create a repo with the name 'my-repo'
2- clone the repo
3- add a file and push it to the server
4- create a tracker item using a git reference to the previous commit in its description (git #my-repo/<commit-hash>)
-> the reference is not clickable

I think we have to look in the function _getExpForRef() in https://tuleap.net/plugins/git/tuleap/tuleap/stable?a=blob&hb=185ee792f6b80bfee00737a8bec3d56f4fc99dbb&h=bde3a200aa714b10d5a82ab5c26e24e865aae6d0&f=src%2Fcommon%2Freference%2FReferenceManager.class.php#L575