Possible busy-polling in MAVServer

[peterkrull]

In the MAVServer:
https://github.com/holsatus/holsatus-flight/blob/main/common/src/mavlink/mod.rs
there may be a busy-polling future somewhere. When running the server in an interrupt-driven executor, it never yields, blocking thread-mode tasks. Likely related to the streamers, since disabling those it does not block other tasks.

[peterkrull]

And the messages do not actually get sent by the streamers..