Should we add types.is_depset?

[allevato]

We're migrating rules_swift to use the types module instead of type(foo) == type(bar), but we can't update all of them since there's not a types.is_depset. I have to check the type because I'm writing action wrappers that need to augment the tools/inputs passed into them, which means knowing whether it's a depset or a list and performing the right operation.

Any reason we shouldn't do this?

[laurentlb]

I think we can add it.