Remove unused @MetricGroup annotation helpers

[schlosna]

Before this PR

Noticed an unnecessary exception due to the unused @MetricGroup and AnnotationHelper code, so ripping this dead code out.

  at java.lang.Throwable.fillInStackTrace([email protected]/Native Method)
  at java.lang.Throwable.fillInStackTrace([email protected]/Throwable.java:799)
  - locked <0x00007f3174f61730> (a java.lang.NoSuchMethodException)
  at java.lang.Throwable.<init>([email protected]/Throwable.java:272)
  at java.lang.Exception.<init>([email protected]/Exception.java:67)
  at java.lang.ReflectiveOperationException.<init>([email protected]/ReflectiveOperationException.java:57)
  at java.lang.NoSuchMethodException.<init>([email protected]/NoSuchMethodException.java:51)
  at java.lang.Class.getMethod([email protected]/Class.java:2201)
  at com.palantir.tritium.event.metrics.annotations.AnnotationHelper.getMethodAnnotation(AnnotationHelper.java:73)
  at com.palantir.tritium.event.metrics.annotations.AnnotationHelper.getMethodAnnotation(AnnotationHelper.java:83)
  at com.palantir.tritium.event.metrics.MetricsInvocationEventHandler.createMethodGroupMapping(MetricsInvocationEventHandler.java:90)
  at com.palantir.tritium.event.metrics.MetricsInvocationEventHandler.<init>(MetricsInvocationEventHandler.java:72)
  at com.palantir.tritium.proxy.Instrumentation$Builder.withMetrics(Instrumentation.java:136)
  at com.palantir.tritium.proxy.Instrumentation$Builder.withMetrics(Instrumentation.java:141)
  at com.palantir.tritium.Tritium.instrument(Tritium.java:44)

After this PR

==COMMIT_MSG==
Remove unused @MetricGroup annotation helpers

This was never used and the code for it has rotted, so time to purge.
The @MetricGroup annotation still exists to prevent any immediate ABI
breaks, but have been deprecated and will be removed in future.
==COMMIT_MSG==

Possible downsides?

[changelog-app]

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Type

• Feature
• Improvement
• Fix
• Break
• Deprecation
• Manual task
• Migration

Description

Remove unused @MetricGroup annotation helpers

This was never used and the code for it has rotted, so time to purge.
The @MetricGroup annotation still exists to prevent any immediate ABI
breaks, but have been deprecated and will be removed in future.

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[svc-autorelease]

Released 0.48.0