Proposed systemd configuration is not valid

[reitzig]

Using the file from the book, I get:

● git-daemon.service - Start Git Daemon
   Loaded: error (Reason: Invalid argument)
   Active: inactive (dead)

Nov 07 13:53:48 name systemd[1]: [/etc/systemd/system/git-daemon.service:5] Executable path is not absolut
Nov 07 13:53:48 name systemd[1]: git-daemon.service: Service lacks both ExecStart= and ExecStop= setting. 

This is on Ubuntu 17.04 with systemd 232. (Yes, I'm aware of the Ubuntu packages git-daemon-run and git-daemon-sysvinit.)

Changing git to /usr/bin/git solves the problem; ExecStop= doesn't seem to be necessary after all.