[Feature] configurable `command` and `args` for containers and initContainers

[saw-jan]

Similar to keycloak helm chart

For example, we could have something similar to this:
seeder-job.yaml, web-deployment.yaml, worker-deployment.yaml:

  initContainers:
      ...
      # command
      {{- if .Values.command }}
      command: {{- .Values.command }}
      {{- end }}
      # args
      {{- if .Values.args }}
      args: {{- .Values.args | default "some-defaults" }}
      {{- end }}

  containers:
      ...
      # command
      {{- if .Values.command }}
      command: {{- .Values.command }}
      {{- end }}
      # args
      {{- if .Values.args }}
      args: {{- .Values.args | default "some-defaults" }}
      {{- end }}

values.yaml:

## @param command Override default container command (useful when using custom images)
##
command: []

## @param keycloakConfigCli.args Args for running the container (set to default if not set). Use array form
##
args: []

Motivation

This allows the user to override the default entrypoint. This can be helpful when using custom images or if the user wants to run some script before the running the services.