overrides: move add(*args) override from Gst.Pipeline to Gst.Bin
overrides: move add(*args) override from Gst.Pipeline to Gst.Bin

GStreamer/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,lubosz/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,lubosz/gst-python,lubosz/gst-python,pexip/gst-python,pexip/gst-python,GStreamer/gst-python,freedesktop-unofficial-mirror/gstreamer__gst-python,pexip/gst-python,GStreamer/gst-python