Add a copy button to copy the SSH shell command

[yiyione]

What would you like to be added:
Add a copy button in job detail page to copy the SSH shell command

Why is this needed:
More easy to copy the SSH command.

Without this feature, how does the current module work:
In current job detail page, user need 3 step to copy the SSH command:

1. click SSH Info button
2. Select the command
3. Right click to copy / press Ctrl + C

Components that may involve changes:
Need a new button in TaskRole table

[suiguoxin]

There could be multiple ssh keys after this feature #5223.
All the user saved public keys along with the public keys for the job will all be saved in the job container.