generate constants for new jupyter notebooks

[lior-antonov]

When creating a new notebook from the ui we should create a cell with default imports and constants:

import hera
PROJECT_NAME = "..."

p = hera.datalayer.Project(projectName=PROJECT_NAME)

# Your code...

maybe even getting all the toolkits that are in the project with:

toolkit1_tk = hera.toolkit.ToolkitHome().getToolkit(<toolkit1Name>, PROJECT_NAME)
toolkit2_tk = hera.toolkit.ToolkitHome().getToolkit(<toolkit2Name>, PROJECT_NAME)
..._tk = hera.toolkit.ToolkitHome().getToolkit(..., PROJECT_NAME)