feat: update terraform-docs/terraform-docs to v0.21.0 #minor

Author: public-glueops-renovatebot[bot]

.devcontainer/Dockerfile

@@ -21,7 +21,7 @@ ARG VERSION_KIND=0.30.0
 # renovate: datasource=github-tags depName=derailed/k9s
 ARG VERSION_K9S=0.50.16
 # renovate: datasource=github-tags depName=terraform-docs/terraform-docs
-ARG VERSION_TERRAFORM_DOCS=0.20.0
+ARG VERSION_TERRAFORM_DOCS=0.21.0
 # renovate: datasource=github-tags depName=doitintl/kube-no-trouble
 ARG VERSION_KUBENT=0.7.3
 # renovate: datasource=github-tags depName=databus23/helm-diff