Bears.py: ask_to_select_capabilities, should return the results from the recursive call

If an invalid number is entered in which case there is a recursive call, now again when a valid number is entered, the results are actually not returned inside the `else` or appended to `selected_capabilities` which results in the returning of an empty list.

difficult/newcomer

Open Bears.py and find ask_to_select_capabilities, then trace the path taken after an invalid number followed by a valid selection. Reproduce that input sequence and inspect the returned value; done means the selected capabilities from the recursive call are preserved instead of producing an empty list.

Written by the indexing model from the issue text.