code: @Override
    public UpdateResponse update(ComplexResourceKey<FlowId, EmptyRecord> key, FlowConfig flowConfig) {
      String flowGroup = key.getKey().getFlowGroup();
      String flowName = key.getKey().getFlowName();
      FlowId flowId = new FlowId().setFlowGroup(flowGroup).setFlowName(flowName);
      return this.flowConfigsResourceHandler.updateFlowConfig(flowId, flowConfig);
    }
docs: Update the flow configuration with the specified key. Running flows are not affected.
  An error is raised if the flow configuration does not exist.
  @param key composite key containing group name and flow name that identifies the flow to update
  @param flowConfig new flow configuration
  @return {@link UpdateResponse}