chore(deps): update hashicorp/null requirement from ~> 2.1 to ~> 3.1

Updates the requirements on [hashicorp/null](https://github.com/hashicorp/terraform-provider-null) to permit the latest version.
- [Release notes](https://github.com/hashicorp/terraform-provider-null/releases)
- [Changelog](https://github.com/hashicorp/terraform-provider-null/blob/main/CHANGELOG.md)
- [Commits](hashicorp/terraform-provider-null@v2.1.0...v3.1.0)

---
updated-dependencies:
- dependency-name: hashicorp/null
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <[email protected]>

Author: dependabot[bot]

5-app-infra/modules/env_base/versions.tf

@@ -27,7 +27,7 @@ terraform {
     }
     null = {
       source  = "hashicorp/null"
-      version = "~> 2.1"
+      version = "~> 3.1"
     }
 
     random = {