api.rs: Correct use for ConnectionItem
api.rs: Correct use for ConnectionItem

Error introduced with previous commit, uncaught as it only shows
up if you compile with `--features dbus_enabled`.

Signed-off-by: Tony Asleson <1ef2d381aa56d512126ddaacc29e68136e4fdf55@redhat.com>

trgill/stratisd,stratis-storage/stratisd,stratis-storage/stratisd,mulkieran/stratisd,mulkieran/stratisd,stratis-storage/stratisd,trgill/stratisd