Avoid breaking permissions by accidental provider upgrade (#40)

* Add stop sign for avoiding breaking permissions by accidental provider upgrade

Author: larstobi

versions.tf

@@ -1,4 +1,9 @@
-
 terraform {
   required_version = ">= 0.12"
+
+  required_providers {
+    aws = {
+      version = ">= 2.0.0, < 3.0.0"
+    }
+  }
 }