Add new run type "triggered" to distinguish manual DAG runs and triggered runs

[molcay]

Add new run type "triggered" to distinguish manual DAG runs and triggered DAG runs (TriggerDagRunOperator).

Justification to introduce a new RunType

Before this improvement, we were prepending the run id with the string "manual" for TriggerDagRunOperator as well as manual run (which can be started on UI). This can cause a misunderstanding when we look for the logs and also for the UI. We did not have a way to distinguish manual runs and the triggered runs (which can be done with TriggerDagRunOperator).

To accomplish this, I introduced the followings:

• A new RunType value:

TRIGGERED = "triggered"

• A new icon for UI:

  import { MdBolt } from "react-icons/md";
  // ...
      case "triggered":
        return <MdBolt style={iconStyle} {...rest} />;
  //...

  which is look likes the following (in action):
  

  Of course, we can change the icon with another icon that can be more suitable but as a entry point, I selected this one.

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