[elasticsearch] Add scope configuration option for metricsets

[legoguy1000]

What does this PR do?

Add scope configuration option for metricsets

Checklist

• I have reviewed tips for building integrations and this pull request is aligned with them.
• I have verified that all data streams collect metrics or logs.
• I have added an entry to my package's changelog.yml file.
• I have verified that Kibana version constraints are current according to guidelines.

Author's Checklist

• [ ]

How to test this PR locally

Related issues

• Closes Elasticsearch (Experimental) Module Doesn't have ability to set scope: cluster #3255

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• Start Time: 2022-05-10T15:33:08.619+0000

• Duration: 4 min 53 sec

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[andrewkroh]

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• Start Time: 2022-06-09T10:04:51.131+0000

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Test	Results
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Passed	31
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Total	31

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[legoguy1000]

THe test never seemed to run for this

[klacabane]

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[klacabane]

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (0/0)	💚
Files	100.0% (0/0)	💚 3.546
Classes	100.0% (0/0)	💚 3.546
Methods	49.057% (26/53)	👎 -40.245
Lines	100.0% (0/0)	💚 9.328
Conditionals	100.0% (0/0)	💚

[klacabane]

Verified the property was properly injected in the agent configuration and in the metricsets (with force: set an invalid scope value and made sure this path was triggered :))

LGTM, thanks @legoguy1000

$ cat state.yml|grep scope -C 5
        id: elasticsearch/metrics-elasticsearch.cluster_stats-dd974da8-2d3f-4ac6-a504-44ce05931f1f
        metricsets:
        - cluster_stats
        password: changeme
        period: null
        scope: node
        username: elastic
      type: elasticsearch/metrics
      use_output: default
    output_permissions:
      default: