Revert cty minor version v1.13 upgrade

[apparentlymart]

We inadvertently incorporated the new minor release of cty into the 1.4 branch, and that's introduced some more refined handling of unknown values that is too much of a change to introduce in a patch release.

Therefore this reverts back to the previous minor release for the v1.4 series, and then we'll separately get the main branch ready to work correctly with the new cty before Terraform v1.5.

This reverts just the upgrade and the corresponding test changes from #32775, while retaining the HCL upgrade and the new test case it introduced for that bug it was trying to fix. That new test is still passing so it seems that the cty upgrade is not crucial to that fix.

[hashicorp-cla]

All committers have signed the CLA.

[apparentlymart]

This might repair #32853, but not clear yet because we've not reproduced that one to determine how a non-collection type is ending up in the setproduct function.

[jbardin]

I can confirm the change fixes 32853. Not certain what is going on exactly, but a DynamicPseudoType being passed into the impl as the return type, which panics when we fetch the element type.

[github-actions]

Reminder for the merging maintainer: if this is a user-visible change, please update the changelog on the appropriate release branch.

[github-actions]

I'm going to lock this pull request because it has been closed for 30 days ⏳. This helps our maintainers find and focus on the active contributions.
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