Thread started/finished logging incur significant overhead when executing many JMeter threads

### Expected behavior

JMeter should support cases when the test produces many threads.

It should probably discard "Thread started", and "Thread is done" messages when the thread startup rate exceeds a certain threshold.

### Actual behavior

JMeter executes ~5-10K requests per second only, and it spends significant time on logging "Thread started" and "Thread is done" messages (they synchronize on the logger, and they cause logging pane updates in the UI).

A workaround is to adjust the `org.apache.jmeter.threads.JMeterThread` logging category to `warning` level.

### Steps to reproduce the problem

Create Open Model Thread Group with debug sampler.
Use `rate(100000/sec) random_arrivals(60 sec)` for the schedule

### JMeter Version

5.5

### Java Version

_No response_

### OS Version

_No response_