tracers: buffer-lateness: add argument to display only late buffers

Help to easily spot places where buffers are late when plotting big pipelines.

Also display some stats about late buffers.

added Enhancement Tracing labels

assigned to @gstreamer-merge-bot

mentioned in commit gdesmott/gst-plugins-rs@d5740ea8

mentioned in commit gdesmott/gst-plugins-rs@33a1d8de

added 6 commits

• 712f95fe...5b0733d5 - 4 commits from branch gstreamer:main
• d5740ea8 - tracers: buffer-lateness: add argument to display only late buffers
• 33a1d8de - tracers: buffer-lateness: display some stats about late buffers

Compare with previous version

merged