config.provider as an requirement is confusing for new users and the deployment will fail

[jensneuhaus]

What steps did you take and what happened:

Trying to deploy Velero without config.provider being set will not deploy anything. I expected that it still works with e.g. a config like the following, if one has two different providers:

configuration:

    backupStorageLocation:
      provider: aws
       ... 

    volumeSnapshotLocation:
      provider: digitalocean.com/velero

What did you expect to happen:

Clear description in values.yaml file, that the provider is required; a check for it or a better handling if it is not existing.

Anything else you would like to add:

The deployment was not created because of {{- if .Values.configuration.provider -}} check; so I did not have any logs and it was hard to find out what actually is the problem.

Environment:

• helm version (use helm version): 3.7.1
• helm chart version and app version: 2.26.1
• Kubernetes version (use kubectl version): Server 1.21.5 (on Server)
• Cloud provider or hardware configuration: Digital ocean

[jenting]

Related to #269

[jenting]

We deprecated the configuration.provider but configured the provider in each backup storage location as well as in each volume snapshot location. Here is the PR.

Closing it.