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ARROW-17214: [C++] Add scalar casts to string types for list based types (#13737)

Following https://lists.apache.org/thread/rp7vpjtt4lgtjxj35oyjyqh9b6on94jf discussion, here is the PR corresponding to the feature : be able to cast list-like types (maps, lists, fixed-size lists) to string type.

It produces output such as :
list<item: int64>{null, 1}
map<string, int64>{{key:string = a, value:int64 = 2}, {key:string = b, value:int64 = 45}}
map<struct<x: int16, y: bool>, int64>{{key:struct<x: int16, y: bool> = {x:int16 = 884, y:bool = true}, value:int64 = 2}, {key:struct<x: int16, y: bool> = {x:int16 = 874, y:bool = false}, value:int64 = null}}
fixed_size_list<item: float>[3]{4, 5, 6}

I tried to be coherent with the rest of the CastTo methods.
Feel free to comment.

Lead-authored-by: LouisClt <louis1110@hotmail.fr>
Co-authored-by: Louis CALOT <calot@isdom.isoft.fr>
Co-authored-by: David Li <li.davidm96@gmail.com>
Signed-off-by: David Li <li.davidm96@gmail.com>