Remove Spanned and add Format trait to Punctuated

[eureka-cpu]

This PR removes the Spanned trait in favor of the Format trait to allow dynamic formatting for type T and P on Punctuated.

[sezna]

would it be possible to add some more tests specific to the behavior of punctuated lists?

[eureka-cpu]

would it be possible to add some more tests specific to the behavior of punctuated lists?

There's a few other examples that I need to add yes, but they require a good bit of refactoring so I am adding them on a separate PR.

[eureka-cpu]

would it be possible to add some more tests specific to the behavior of punctuated lists?

There's a few other examples that I need to add yes, but they require a good bit of refactoring so I am adding them on a separate PR.

To add clarity to this, the refactoring is in regards to enum, struct and storage that also use Punctuated but at present they are handled inside of their respective format() functions instead of in Punctuated::format().

[kayagokalp]

lgtm