[RPD-289] Update the Chroma Terraform within the LLM stack to use Helm

[Christopher-Norman]

This PR modifies the Chroma Terraform code for Kubernetes deployment to use Helm deployment instead of Terraform kubernetes_deployment modules. These changes have been made to be consistent with other server deployments on Kubernetes.

Note: This PR is an optional change.

Checklist

Please ensure you have done the following:

• [x] I have read the CONTRIBUTING guide.
• [x] I have updated the documentation if required.
• [ ] I have added tests which cover my changes.

Type of change

Tick all those that apply:

• [ ] Bug Fix (non-breaking change, fixing an issue)
• [x] New feature (non-breaking change to add functionality)
• [ ] Breaking change (fix or feature that would cause existing functionality to change)
• [ ] Other (add details above)