Added allow capital letter in dependency name

[turdusmerula]

I am deploying the Authentik helm chart with pyhelm3 and I receive an error I think is not okay.

Inside the values.yaml file there is the following block:

serviceAccount:
  # -- Create service account. Needed for managed outposts
  create: true
  # -- additional service account annotations
  annotations: {}
  serviceAccountSecret:
    # As we use the authentik-remote-cluster chart as subchart, and that chart
    # creates a service account secret by default which we don't need here,
    # disable its creation
    enabled: false
  fullnameOverride: authentik

The dependency name serviceAccount does not validate with the rule r"^[a-z0-9-]+$" from models.py:42 because it contains a capital letter.
However the chart deploys perfectly fine with helm3 with no issue on the capital letter for the dependency name, I think the correct rule should be r"^[a-zA-Z0-9-]+$"which corrects the error I'm facing

[voidlily]

I'm also seeing this with the policy-reporter helm chart and the kyvernoPlugin dependency. This PR would fix that chart as well.

[JohnGarbutt]

I think the problem we have is this type gets re-used in a few too many places. Its based on this documentation:
https://helm.sh/docs/chart_best_practices/conventions/#chart-names

I think we need to rework this one, potentially.