Add a notebook specific label

[DharmitD]

Why you need this feature:

Right now, there's just one label opendatahub.io/dashboard=true for notebooks. Adding an explicit notebook specific static label would help us utilize the notebook component effectively.

Describe the solution you'd like:

For instance, we're trying to update the Data Science Pipelines' network policy to connect to the notebook pod. In this case, having an exclusive static label would be really helpful.

[harshad16]

Moved to JIRA: https://issues.redhat.com/browse/RHOAIENG-2220
closing this issue.
please check it out details there.