discovery.process: Accept failing username detection

[simonswine]

Quite common with docker container UIDs not resolving on the host or in another container.

This will basically move on in those cases, rather than dropping the whole process.

Unsure if this should also be a lower level log message, potentially only debug.

[ptodev]

Unsure if this should also be a lower level log message, potentially only debug.

Maybe a warning? I'm actually surprised that if any of those fails, the discovery for that process as a whole gives up. I thought it'd be all best effort? It'd be good to document this in the discover_config block docs too.

[simonswine]

Maybe a warning? I'm actually surprised that if any of those fails, the discovery for that process as a whole gives up. I thought it'd be all best effort? It'd be good to document this in the discover_config block docs too.

@tpaschalis In the latest revision I am actually filtering this error all together.

We need to continue for missing executable, cwd, and cmdline, as this is a sign that we have a kernel level process.