override host on statsd metricset

[aspacca]

Enhancement

What does this PR do?

It adds Host() implementation for statsd metricset

Why is it important?

Host() returns the hostname or other module specific value that identifies a specific host or service instance from which to collect metrics.
In the BaseMetricSet implementation it uses the hosts field from config of the metricset.
statsd rather use host and port, so a different implementation is needed to report relevant information

Checklist

• My code follows the style guidelines of this project
• I have commented my code, particularly in hard-to-understand areas
  - [ ] I have made corresponding changes to the documentation
  - [ ] I have made corresponding change to the default configuration files
  - [ ] I have added tests that prove my fix is effective or that my feature works
• I have added an entry in CHANGELOG.next.asciidoc or CHANGELOG-developer.next.asciidoc.

Author's Checklist

• [ ]

How to test this PR locally

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Logs

{"log.level":"debug","@timestamp":"2021-11-23T18:44:13.426+0100","log.logger":"module","log.origin":{"file.name":"module/wrapper.go","file.line":189},"message":"Starting metricSetWrapper[module=statsd, name=server, host=127.0.0.1:8125]","service.name":"metricbeat","ecs.version":"1.6.0"}

{"log.level":"debug","@timestamp":"2021-11-23T18:45:37.777+0100","log.logger":"module","log.origin":{"file.name":"module/wrapper.go","file.line":189},"message":"Starting metricSetWrapper[module=airflow, name=statsd, host=127.0.0.1:8126]","service.name":"metricbeat","ecs.version":"1.6.0"}

[mergify]

This pull request does not have a backport label. Could you fix it @aspacca? 🙏
To fixup this pull request, you need to add the backport labels for the needed
branches, such as:

• backport-v./d./d./d is the label to automatically backport to the 7./d branch. /d is the digit

NOTE: backport-skip has been added to this pull request.

[elasticmachine]

Pinging @elastic/integrations (Team:Platforms)

[elasticmachine]

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• Start Time: 2021-11-23T17:49:31.112+0000

• Duration: 107 min 33 sec

• Commit: f7e664d

Test stats 🧪

Test	Results
Failed	0
Passed	9755
Skipped	2528
Total	12283

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