Show more details about the pipeline runing status

Created by: LinuxSuRen

What would you like to be added: Show more details about the pipeline running status. It's necessary especially when the Jenkins agent was not ready.

Why is this needed: Users will feel confused if there's nothing until the Pipeline get started running. Sometimes the Jenkins agent has no chance to run due to some issues. For example, configuration errors of the PodTemplate, or the CPU or memory is insufficient.

The good news is that we already can get the block reason from the back-end API.

We can use the below message via this API http://xxx.xxx.xxx.xxx:30880/kapis/devops.kubesphere.io/v1alpha2/devops/goodkjclz/pipelines/simple/runs/1/. But the message, please member that you will get different language according to different browser setting.

...
"causeOfBlockage": "All nodes of label ‘go’ are offline",
...

Here's a screenshot of what I'm trying to explain.

/area devops /kind feature