GESTimeline: minor cleanup
GESTimeline: minor cleanup

freesteph/gst-editing-services,luisbg/gst-editing-services,pitivi/gst-editing-services,cfoch/gst-editing-services,MathieuDuponchelle/PitiviGes,volodymyrrudyi/gst-editing-services,MathieuDuponchelle/PitiviGes,ahmedammar/platform_external_gst_editing_services,cfoch/gst-editing-services,pitivi/gst-editing-services,ahmedammar/platform_external_gst_editing_services,pitivi/gst-editing-services,volodymyrrudyi/gst-editing-services,cfoch/gst-editing-services,cfoch/ges,cfoch/ges,luisbg/gst-editing-services,volodymyrrudyi/gst-editing-services,freesteph/gst-editing-services,cfoch/ges,MathieuDuponchelle/PitiviGes,MathieuDuponchelle/PitiviGes,cfoch/ges,cfoch/gst-editing-services,freesteph/gst-editing-services,pitivi/gst-editing-services