standard_module_structure: update docs link (#1000)

Author: bendrucker

docs/rules/terraform_standard_module_structure.md

@@ -23,7 +23,7 @@ Reference: https://github.com/terraform-linters/tflint/blob/v0.16.0/docs/rules/t
 
 ## Why
 
-Terraform's documentation outlines a [Standard Module Structure](https://www.terraform.io/docs/modules/index.html#standard-module-structure). A minimal module should have a `main.tf`, `variables.tf`, and `outputs.tf` file. Variable and output blocks should be included in the corresponding file.
+Terraform's documentation outlines a [Standard Module Structure](https://www.terraform.io/docs/modules/structure.html). A minimal module should have a `main.tf`, `variables.tf`, and `outputs.tf` file. Variable and output blocks should be included in the corresponding file.
 
 ## How To Fix