Set GOMEMLIMIT when running in a containerized environment

[marclop]

Descripiton

how do we look at setting soft memory limit for apm-server https://pkg.go.dev/runtime/debug#SetMemoryLimit based on total memory %.

@1pkg brought up that we should probably be setting GOMEMLIMIT to 85-90% of the container memory limit (or the detected total memory when not running in containerized environments). It would avoid the APM server running out of memory when memory usage approaches that GOMEMLIMIT.

If GOMEMLIMIT is set, then we should respect the setting and not set it ourselves in the code.

Arguably, this is something that elastic-agent could do, but if we do it in APM Server, then this limit would apply to the process regardless of the mode/manner it is run.