* Allow terraform-provider-ct versions v0.6+ (e.g. v0.7.1)
Before, only v0.6.x point updates were allowed
* Update terraform-provider-ct to v0.7.1 in docs
* READ the docs before updating terraform-provider-ct,
as changing worker user-data is handled differently
by different cloud platforms
* Mark `kubeconfig` and `asset_dist` as `sensitive` to
prevent the Terraform CLI displaying these values, esp.
for CI systems
* In particular, external tools or tfvars style uses (not
recommended) reportedly display all outputs and are improved
by setting sensitive
* For Terraform v0.14, outputs referencing sensitive fields
must also be annotated as sensitive
Closes https://github.com/poseidon/typhoon/issues/884
* CoreOS Container Linux was deprecated in v1.18.3
* Continue transitioning docs and modules from supporting
both CoreOS and Flatcar "variants" of Container Linux to
now supporting Flatcar Linux and equivalents
Action Required: Update the Flatcar Linux modules `source`
to replace `s/container-linux/flatcar-linux`. See docs for
examples
