code: private StoreKey getTargetKey( final String targetName )
      {
          return targetGroupKeyMap.computeIfAbsent( targetName,
                                                    k -> new StoreKey( MavenPackageTypeDescriptor.MAVEN_PKG_KEY,
                                                                       StoreType.group, targetName ) );
      }
docs: Provides target group store key for a given group name. This is meant to provide the same instance of the key
  for a name to be able to synchronize promotion requests based on this instance.
  
  @param targetName the target group name
  @return the group store key