helm values for health checks not configurable in unleash-edge

[I3uckwheat]

Describe the feature request

I want to be able to edit the helm values for the livenessProbe and redinessProbe urls.

Background

Currently the environment variable for the BASE_PATH will allow overwriting of the base path for unleash-edge. This can cause a situation where your health checks are actually at /BASE_PATH/internal-backstage/health and you cannot deploy using the provided helm chart for unleash-edge. In unleash itself, it allows for changing the base path, as well as changing the health-check paths to allow for a base path change.

Solution suggestions

1. Update the deployment.yaml file to allow for configuration in the values.yaml file for the livenessProbe and redinessProbe values, much like unleash's helm charts
2. Update the deployment.yaml file to use the readiness command outlined in the documentation here
   1. This may require an update to the utility that is called to utilize the BASE_PATH environment variable

PR for the first solution: #97

[I3uckwheat]

This is actively blocking our use of Unleash as we have to use a subroute for this with our current ecosystem and a subdomain is not really an easy option.

[bcampbellGG]

We ran into the same issue trying to host unleash-edge with a custom base path, we ended up just forking the chart to modify the .yaml file, this would be a useful addition to have though.