This brings in the new HCL extension functions "try", "can", and
"convert", along with the underlying HCL and cty infrastructure that allow
them to work.
This also includes an upgrade to cty v1.1.1 because HCL calls for it.
The changes in these two libraries are mainly to codepaths that don't
directly affect Terraform, but including this upgrade will cause some
small improvements to Terraform's error messages for type conversion
problems.
Martin Atkins