Displayelapsetimeforlongrunningparagraph

What is this PR for?

For long running paragraph, it is hard to know how long it has already been running. We should either have the elapsed time displayed

What type of PR is it?

[Bug Fix ]

Todos

What is the Jira issue?

ZEPPELIN-704 (https://issues.apache.org/jira/browse/ZEPPELIN-704)

How should this be tested?

-Open a note.
-Run a paragraph , It should show you the elapsed time.

Screenshots (if appropriate)

Questions:

• Does the licenses files need update?No


• Is there breaking changes for older versions?No


• Does this needs documentation?No

该提问来源于开源项目：apache/zeppelin