Truncate id hash to 10 chars

**This is take 2 of trying to fix this The first was reverted because it broke tests (see [here](https://github.com/saltstack/salt/commit/a39f3f6cbf1788a59f78dde5d7836c0cefe6ad7b#commitcomment-6423523)). Let's see if this works.**

This helps avoid the sock path being longer than the max length allowed
by the kernel. See the following comment for more information:

https://github.com/saltstack/salt/issues/12172#issuecomment-43903643