Ability to stop a pipeline from the UI

[ankitm123]

To stop release and pull request builds we can run:

jx pipeline stop

It would be much more convenient to have this functionality in the UI instead (Every CI/CD tool in the market has this functionality, so it's not something new)

[rajatgupta24]

I am working on this

[ankitm123]

To be shown in the office hours on Aug 2, 2022

[rajatgupta24]

Todo:

• Need to add a cancel btn in the /pipelines table
• Improve the err handling

[rajatgupta24]

Update, stop pipeline
from pipeline detail page #50
from pipelines page #51

[ankitm123]

We still need to add the functionality to stop pipelines from the pipelines list page.

[rajatgupta24]

We still need to add the functionality to stop pipelines from the pipelines list page.

This PR should implement the stop pipeline #75