Remove deprecated event and reporting interfaces from Metricbeat

[ruflin]

To clean up the Metricbeat and simplify it the old interfaces should be removed. This issue is to track the removal.

• Remove mb.PushReporter interface
  • Convert http/server metricset to PushReporterV2 Refactor http.server metricset  #7100
  • Convert graphite/server metricset to PushReporterV2
  • Convert kubernetes/event metricset to PushReporterV2
• Remove mb.Reporter interface
• Remove mb.ReportingMetricSet interface
• Remove mb.PushMetricSet interface

[ycombinator]

@ruflin Just want to double check that this issue is still relevant?

[ruflin]

@ycombinator Don't know how many of the above already happened, but I think we should still clean this up to remove technical debt, but I let @exekias to chime in here.

[botelastic]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.