This commit adds the definitions of provider protocol 5.8 and 6.8 to our
archive of the historical protocol versions and then adopts each as the
current version of each of its major series.
These MPL-licensed schema definitions are from the plugin protocol server
implementation in this repository, copyright HashiCorp:
https://github.com/hashicorp/terraform-plugin-go
The only modifications made are to change the "option go_package" directive
to match where the stubs need to be generated for OpenTofu, and to claim
copyright for that change and thus make the copyright header consistent
with what our pre-commit rules require.
The regeneration of the Go API stubs for the two major protocol versions
introduces some new fields and messages that OpenTofu does not yet support
but will happily ignore. Future work might make some use of these new
additions, but that's out of scope of this change that is intended only
to synchronize our protocol definition with what new plugin server releases
are likely to be linked against.
Compared to the previous minor releases of each series this only introduces
new fields to existing message types and does not define any new RPC
functions, so we don't need any changes to the "grpcwrap" and "mock_proto"
packages in this case.
Signed-off-by: Martin Atkins <mart@degeneration.co.uk>
