Request: Optional config to warn when a parameter annotation could use `Mapping` instead of `Dict` or `Sequence` instead of `List`

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  Feature request

Basically, I think it would be nice if mypy could warn when the user could be giving their function immutable versions of the argument types instead of mutable ones. For example:

def len_greater_than_three(input_list: List[int]) -> bool: # Warning: Could use read only type Sequence instead of List for parameter 1.
    return len(input_list) > 3

Being prompted to use immutable types when you're not mutating the input could improve the usability of mypy quite a bit since it would result in functions who's parameters are covariant much more often. It's also convenient to know when a function isn't mutating its arguments based on its annotation, and the desire to default to using immutable types wherever possible probably makes sense for a lot of users.

Beginne mit der Durchsicht von Issue #8484 und den bestehenden Diagnose- und Konventionen zur Konfiguration von mypy. Definiere das optionale Warnverhalten für Parameter, die mit veränderlichen Typen annotiert sind, und überprüfe anschließend, dass das Beispiel nur gemeldet wird, wenn der Parameter nicht verändert wird, und dass die Einstellung konfigurierbar ist.