Tempo-distributed helm values typo in comment

[houserx-jmcc]

After struggling through problems stemming from #2802, I believe there was a mistake in one of the final 2 PRs from that issue:

helm-charts/charts/tempo-distributed/values.yaml

Line 428 in ecf2456

# -- For processors to be enabled and generate metrics, pass the names of the processors to `global_overrides.defaults.metrics_generator_processors` value like `[service-graphs, span-metrics]`.

Indicates this structure, which doesn't work (crash loops):

global_overrides:
  defaults:
    metrics_generator_processors: ['service-graphs', 'span-metrics']

but shinebayar-g's comment at the end does work:

global_overrides:
    defaults:
        metrics_generator:
            processors: ['service-graphs', 'span-metrics']