Allow JFR queue size and harvest interval to be configured via agent config

[jtduffy]

Resolves #1511

This is a continuation of @meiao 's PR to:

• Configure JFR queue size via jfr.queue_size - default of 250000
• Configure JFR harvest interval via jrf.harvest_interval - default of 10 seconds
• Send up supportability metrics with the configured JFR queue size and interval values

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 75.00000% with 2 lines in your changes missing coverage. Please review.

Project coverage is 70.69%. Comparing base (925da72) to head (ce22102).

Files with missing lines	Patch %	Lines
.../java/com/newrelic/agent/config/JfrConfigImpl.java	50.00%	2 Missing ⚠️

Additional details and impacted files

@@             Coverage Diff              @@
##               main    #2168      +/-   ##
============================================
- Coverage     70.71%   70.69%   -0.03%     
+ Complexity    10001     9999       -2     
============================================
  Files           842      842              
  Lines         40348    40356       +8     
  Branches       6115     6115              
============================================
- Hits          28534    28528       -6     
- Misses         9063     9075      +12     
- Partials       2751     2753       +2     

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.