Fix Git hooks that push Puppet modules to immerda

Originally created by @intrigeri on #7108 (Redmine)

The solution that was deployed to tails/sysadmin#5500 apparently does not work (anymore?). tails/sysadmin#5500 was blocking important progress (tails/tails#6182), hence marking as priority > normal. And tails/sysadmin#5500 was for 2.0, so flagging this regression for 2.0 too.

Related issues

• Related to tails/sysadmin#5500