[Cloud Security] fix 'got types.Null, expected iterable type' error

[maxcold]

Proposed commit message

Fix 'got types.Null, expected iterable type' error in all Wiz data streams discovered in https://github.com/elastic/security-team/issues/10390

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.

How to test this PR locally

• build package elastic-package build
• run stack elastic-package stack up -v -d
• ingest some Wiz data
• over time there shouldn't be any documents with error.message in the Wiz documents

Related issues

• fixes https://github.com/elastic/security-team/issues/10390

[elasticmachine]

🚀 Benchmarks report

Package wiz 👍(3) 💚(0) 💔(1)

Expand to view

Data stream	Previous EPS	New EPS	Diff (%)	Result
cloud_configuration_finding	5347.59	4184.1	-1163.49 (-21.76%)	💔

To see the full report comment with /test benchmark fullreport

[elasticmachine]

Pinging @elastic/security-service-integrations (Team:Security-Service Integrations)

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 0b9db96

History

• 💔 Build #15823 failed a0ebcbb
• 💔 Build #15822 failed 9b097a0
• 💚 Build #15768 succeeded 34e2102

[elastic-sonarqube]

Quality Gate passed

Issues
0 New issues
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
100.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube

[elasticmachine]

Package wiz - 1.9.0-preview02 containing this change is available at https://epr.elastic.co/search?package=wiz