Comment 9 for bug 2034253

Better use ID from /etc/os-release instead.

https://www.freedesktop.org/software/systemd/man/os-release.html says: "NAME identifies the operating system, without a version component, and suitable for presentation to the user." and "ID is lower-case string (no spaces or other characters outside of 0–9, a–z, ".", "_" and "-") identifying the operating system, excluding any version information and suitable for processing by scripts or usage in generated filenames."