[comment-only] mark OCM provider fields optional

cs3/ocm/provider/v1beta1/resources.proto

@@ -81,19 +81,19 @@ message ProviderInfo {
  // REQUIRED.
  // The full name of the provider.
  string full_name = 2;
- // REQUIRED.
+ // OPTIONAL.
  // A description of the provider.
  string description = 3;
- // REQUIRED.
+ // OPTIONAL.
  // The organization to which the provider belongs.
  string organization = 4;
  // REQUIRED.
  // The domain of the sync'n'share provider.
  string domain = 5;
- // REQUIRED.
+ // OPTIONAL.
  // The homepage of the provider.
  string homepage = 6;
- // REQUIRED.
+ // OPTIONAL.
  // The email at which the provider can be reached.
  string email = 7;
  // REQUIRED.