Add jvm.file_descriptor.count metric to the instrumentation/runtime-telemetry #13757
Description
Is your feature request related to a problem? Please describe.
This is a follow-up of #13722, where we added a metric to jvm.yaml but its unused in the instrumentation/runtime-telemetry.
Opening this PR so that this issue is not lost
Describe the solution you'd like
Feel free to assign myself to this issue. I will try to get to it over the next week!
Describe alternatives you've considered
No response
Additional context
No response