[8.18] (backport #9827) fix: correct spelling of 'output' in various templates and monitoring code

[mergify]

What does this PR do?

Just some small typo fixes in variable names.

Why is it important?

N/A

Checklist

• I have read and understood the pull request guidelines of this project.
• 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/fragments using the changelog tool
• I have added an integration test or an E2E test

Disruptive User Impact

N/A

How to test this PR locally

N/A

Related issues

N/A

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This is an automatic backport of pull request #9827 done by [Mergify](https://mergify.com).

[elasticmachine]

Pinging @elastic/elastic-agent-control-plane (Team:Elastic-Agent-Control-Plane)

[elastic-sonarqube]

Quality Gate passed

Issues
1 New issue
0 Fixed issues
0 Accepted issues

Measures
0 Security Hotspots
66.7% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarQube

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: 9402398

cc @nkvoll

[mergify]

This pull request has not been merged yet. Could you please review and merge it @nkvoll? 🙏

[ebeahan]

@kaanyalti can you take a look at this backport?