Add annotations to frontend helm template.

[senthilkumarkj]

This is similar to annotations in backend template at https://github.com/tidaltech/cvat/blob/develop/helm-chart/templates/cvat_backend/service.yml#L10-L13

Motivation and context

To enable setting annotations to frontend service similar to backend service. Closes #6161

How has this been tested?

I've tested this in my k8s setup.

Checklist

• I submit my changes into the develop branch
• [-] I have added a description of my changes into the [CHANGELOG] (https://github.com/opencv/cvat/blob/develop/CHANGELOG.md) file - Not sure if it's worth adding.
• [-] I have updated the documentation accordingly
• [-] I have added tests to cover my changes
• I have linked related issues (see GitHub docs)
• [-] I have increased versions of npm packages if it is necessary
  (cvat-canvas,
  cvat-core,
  cvat-data and
  cvat-ui)

License

• I submit my code changes under the same MIT License that covers the project.
  Feel free to contact the maintainers if that's a concern.

[nmanovic]

@senthilkumarkj , Thank you for the contribution!