improve docs on how to use condition filters

[gsantoro]

What does this PR do?

Improve docs on how to use condition filters for datastreams.

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.

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• Start Time: 2023-03-20T13:36:21.553+0000

• Duration: 29 min 17 sec

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Test	Results
Failed	0
Passed	144
Skipped	0
Total	144

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (1/1)	💚
Files	100.0% (3/3)	💚
Classes	100.0% (3/3)	💚
Methods	94.928% (131/138)	👍 1.594
Lines	97.472% (347/356)	👎 -2.528
Conditionals	100.0% (0/0)	💚

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