chore(docs): Create runbook to update Chart dependency

[javirln]

This pull request adds a comprehensive runbook for upgrading Helm chart dependencies in the Chainloop project. The runbook provides strict guidelines for upgrade types, version compatibility, and step-by-step instructions to ensure upgrades are performed safely and consistently. It also includes troubleshooting, rollback, and escalation procedures to help maintain system stability during chart upgrades.

Documentation: Helm Chart Upgrade Process

• Added a detailed runbook (docs/runbooks/chart-upgrade-process.md) describing the upgrade process for Chainloop Helm chart dependencies, including PostgreSQL, Vault, and Dex.

Upgrade Guidelines and Restrictions

• Defined strict rules for patch, minor, and major version upgrades, explicitly forbidding major upgrades without manual review and escalation.
• Provided mandatory version compatibility checks and stop conditions to prevent unsafe upgrades.

Step-by-Step Upgrade Procedures

• Outlined separate processes for specific image upgrades and minor chart upgrades, including commands for validation, chart extraction, image update, and dependency management.
• Included checklist for pre-upgrade, during upgrade, and post-upgrade stages to ensure completeness and safety.

Verification, Troubleshooting, and Emergency Procedures

• Added verification steps (linting, testing, image consistency checks), troubleshooting guides for common issues, and emergency rollback and escalation instructions.

[migmartri]

I'd make sure we do not upgrade container images without updating the chart, we always must upgrade the chart, the trick is to find which version of the chart