Cleanups for Reports Notebook

[amuolo]

This ticket is about a number of cleanups for the notebook Reports of the IFRS 17 Template Project:
a. With the automatic height feature of the new reports we don't need anymore to specify with { Height } for all the reports.
b. The Actuarial Experience Adjustment has already the columns sliced by Amount Type, hence we can remove the suggestion in the commented part.

[dcolleoni]

Hi @amuolo,
about point b, the suggestion is not to add AmountType but to add GroupOfContract and AmountType.
Adding AmountType after GroupOfContract allows the user to control the order of the sliced column and get a better understanding of the reported values.

I suggest to remove point b from this issue or to reformulate it to provide a better description of the suggested code.