Add definitions for package dependencies

[jsoriano]

What does this PR do?

Add definitions for package dependencies, fixes #1083.

Integration packages can depend on content and input packages. Input packages will be resolved on build time, while content packages will be installed before installing the integration package.

This change includes:

• New requires field in manifests to define dependency packages.
• New requires field in test configuration to pin packages on tests.
• New package field in policy templates and data streams to reference input packages.
• Validations to ensure consistency between these values.

Assisted by Copilot

Why is it important?

Allow to reuse definitions between packages.

Checklist

• I have added test packages to test/packages that prove my change is effective.
• I have added an entry in spec/changelog.yml.

Related issues

• Part of https://github.com/elastic/ingest-dev/issues/6495
• Closes [Change Proposal] Add support for dependencies in integration packages #1083

[elasticmachine]

💚 Build Succeeded

• Buildkite Build
• Commit: a6a57e0

History

• 💚 Build #1857 succeeded 3842f39
• 💚 Build #1839 succeeded 98a7615
• 💔 Build #1838 failed aeb0e91
• 💔 Build #1837 failed e0d1319
• 💚 Build #1796 succeeded ec76776

cc @jsoriano