Iterate on Python walkthrough experiment

[luabud]

Python dev walkthrough

• Enable it to 100% of folks on our insiders version
• Ramp up to 50% of folks using our stable version
• Ramp up to 100%

Python data science walkthrough

• Enable it to 100% of folks on our insiders version
• Ramp up to 50% of folks using our stable version
• Decide if we will ramp up to 100% of shut it down (Will we keep the data science walkthrough as a separate tile or should we merge it with the Python for development one?  #17193)
  • We'll reframe the experiment in control tower to enable it alongside the Python extension