packaging: Drop git option from spec %autosetup

The most recent Fedora dist-git PR failed on this. We don't need it, and
it's discouraged by the packaging guidelines [1].

[1] https://docs.fedoraproject.org/en-US/packaging-guidelines/#_autosetup

packaging/python-dbusmock.spec

@@ -34,7 +34,7 @@ Requires: python3-dbus, python3-gobject, dbus-x11
 %description -n python3-dbusmock %_description
 
 %prep
-%autosetup -n %{name}-%{version} -S git
+%autosetup -n %{name}-%{version}
 rm -rf python-%{modname}.egg-info