[cloud_security_posture] Ensure event.kind is correctly set for pipeline errors

[MakoWish]

What does this PR do?

Modify cloud_security_posture integration to correctly set event.kind for pipeline errors and ensure error.message is an array.

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

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How to test this PR locally

Related issues

• For sei: ensure packages set error.kind to "pipeline_error" in on_failure processor #6582

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• Start Time: 2023-08-10T22:28:49.277+0000

• Duration: 15 min 24 sec

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Test	Results
Failed	0
Passed	4
Skipped	0
Total	4

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[oren-zohar]

Thank you 🙏

[MakoWish]

@oren-zohar, can you /test again? I don't have permissions to.

[oren-zohar]

/test

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🌐 Coverage report

Name	Metrics % (covered/total)	Diff
Packages	100.0% (0/0)	💚
Files	100.0% (0/0)	💚
Classes	100.0% (0/0)	💚
Methods	25.0% (2/8)	❕
Lines	100.0% (0/0)	💚
Conditionals	100.0% (0/0)	💚

[elasticmachine]

Package cloud_security_posture - 1.5.0-preview31 containing this change is available at https://epr.elastic.co/search?package=cloud_security_posture

[elasticmachine]

Package cloud_security_posture - 1.5.0 containing this change is available at https://epr.elastic.co/search?package=cloud_security_posture