The template files in the `build-aux` directory used in enums sources
and headers generation use the `{$name}-template.[ch]` pattern.
However, the examples in the official guide[0] and usually GNOME and
Freedesktop packages use the `{$name}.[ch].template` pattern.
Due to this, the name of the template files and build commands have
been changed.
[0] https://developer.gnome.org/gobject/stable/glib-mkenums.html
