Update Calibration.ipynb

[mjpelmear]

Apparently the function name changed at some point.

[FranzForstmayr]

Good Catch!
Usually the notebooks should get executed after each PR, but obviously this one wasnt.
We should find the reason why this notebook is exclude from testing.

[Ttl]

It looks like all of the cells in this notebook are markdown and there is no executable code. This should be rewritten so that the code is actually executed.

[jhillairet]

Yes indeed, that's because it's a generic explanation, not a specific example. But eventually it can be transformer to a practical example.

Thank you @mjpelmear !