chore: update firewall image to 2.9.7

[socket-release-bot]

Updates deployment defaults to the published Socket Firewall image 2.9.7 and bumps the Helm chart patch version.

Image: socketdev/socket-registry-firewall:2.9.7
Release run

Manual review is required before merging:

• Review the release changes for configuration or behavioral changes.
• Update deployment documentation and migration examples where needed.
• Check the Helm chart version and CloudFormation defaults, including other pending version PRs.

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Note

Low Risk
Documentation and default version pins only; runtime behavior changes only if operators upgrade to these defaults—review the 2.9.7 release notes for any config or behavior deltas before merging.

Overview
Bumps the default Socket Registry Firewall container image from 2.9.3 to 2.9.7 and the Helm chart patch from 0.11.7 to 0.11.8, keeping Chart.yaml appVersion aligned with the pinned image.

The same defaults are updated in helm/values.yaml, CloudFormation firewall-eks.yaml parameters (ChartVersion, FirewallImageTag), the EKS example dns-override.values.yaml, and the related README tables so greenfield Helm and CloudFormation handoff installs stay on the new release without drift.

^{Reviewed by Cursor Bugbot for commit d95b2c1. Configure here.}