Upgrade uStreamer to v6.5X

[jotaen4tinypilot]

Our current uStreamer version (v6.36) is roughly 1 year old. In order to not fall behind too much, we should upgrade to a more recent version, e.g. v6.50 or higher.

Maybe it would make sense to also look into tiny-pilot/janus-debian#25 right away.

[db39]

Related: https://github.com/tiny-pilot/tinypilot-pro/issues/1806