Merge pull request #31689 from hashicorp/backport/remove-future-statement-import/briefly-viable-glowworm

Backport of Remove future-facing statement from import page into v1.2

set PRODUCT_VERSION for default docker build

This fixes a possible panic in what Terraform calls the "flatten" function
in situations where a user passes in a null value of a sequence type.
The function will now treat that the same as a null value of any other
type.

This gets us a sufficiently-new "stringer" tool that it's able to work
when there are packages in our dependency graph that use Go 1.18 type
parameters.

Without this, we will see the following error the first time we introduce
any dependency that uses type parameters, even if that dependency isn't
involved in our "stringer-ing".
    stringer: Unexpected package creation during export data loading

Backport of docs: Fix condition example into v1.2

Backport of docs: Use more consistent naming in Module Registry Protocol documentation into v1.2

Backport of doc: use american english into v1.2

Merge pull request #31612 from hashicorp/backport/jbardin/static-validate-warnings/initially-steady-rattler

Backport of don't lose warnings from static validation into v1.2

Co-authored-by: Katy Moe <katy@katy.moe>

v1.2 backport of 31576

We can't validate that data from deprecated nested attributes is used in
the configuration, but we can at least catch the simple case where a
deprecated attribute is referenced directly.

Merge pull request #31603 from hashicorp/backport/jbardin/static-validate-nested-types/possibly-crack-mouse

Backport of Account for `NestedType` in static traversal validation into v1.2

Co-authored-by: Kevin Wang <kwangsan@gmail.com>

Co-authored-by: Kevin Wang <kwangsan@gmail.com>

Backport of update json plan docs with drift output into v1.2