85fa81c7c8
Using g_error() crashes the application, producing a coredump e.g. when the user closes the video window, which can be confusing (especially on the very first tutorial). Let's change this to log the error message without crashing, using g_printerr(), like subsequent tutorials. Part-of: <https://gitlab.freedesktop.org/gstreamer/gstreamer/-/merge_requests/6883>