Update dependency to github.com/go-viper/mapstructure/v2

[mikelolasagasti]

Module github.com/go-viper/mapstructure/v2 is the blessed fork for module github.com/mitchellh/mapstructure as annoucned by Mitchell Hashimoto in
https://gist.github.com/mitchellh/90029601268e59a29e64e55bab1c5bdc

Alpha version is just the module rename
go-viper/mapstructure@v1.6.0...v2.0.0-alpha.1

[cipherboy]

@mikelolasagasti what's your thoughts on removing this dependency?

[mikelolasagasti]

As module github.com/mitchellh/mapstructure won't be maintained anymore and there is a blessed fork, I though it would be a good idea to adopt it for better future maintenance.

The 2.0.0-alpha1 version of the new module is just the rename of the original module.

OpenTofu accepted the PR I sent a few weeks ago.

[cipherboy]

@mikelolasagasti Right, but I'm wondering if we'd be better off removing this dependency anyways.

I think we mostly considered its use as deprecated; there were a few places where we'd use it for compatibility, but in general, new uses should not have used it. This is especially true in the public facing APIs: we preferred explicit serialization over automatic serialization of the underlying datastructure, as it makes incremental breaking changes harder (e.g., if we change from an int -> time.Duration in the underlying datastructure, it is easier to provide request/response compatibility if we own the serialization ourselves).

This isn't about whether it'd be good to adopt this, but whether we can simplify and remove it altogether. :-) But perhaps best we adopt this in the interim and remove usage of this and github.com/fatih/structs long-term.