feat: add the region in variables and explain how to show the list of existing regions (#91)

Author: scraly

storage/s3-with-tf/README.md

@@ -7,6 +7,10 @@ export AWS_ACCESS_KEY_ID="<your_access_key>"
 export AWS_SECRET_ACCESS_KEY="<your_secret_access_key>"
 ```
 
+To define the region (depending on our needs), follow this guide:
+https://help.ovhcloud.com/csm/en-gb-public-cloud-storage-s3-location?id=kb_article_view&sysparm_article=KB0047382
+
+And then update the region variable in the `variables.tf` file.
 
 Run the TF command `terraform apply`:
 ```bash

storage/s3-with-tf/provider.tf

@@ -8,14 +8,14 @@ terraform {
 
 # Configure the AWS Provider
 provider "aws" {
-  region     = "gra"
+  region     = "${var.region}"
 
   # OVH implementation has no STS service
   skip_credentials_validation = true
   skip_requesting_account_id  = true
   # the gra region is unknown to AWS hence skipping is needed.
   skip_region_validation = true
   endpoints {
-    s3 = "https://s3.gra.io.cloud.ovh.net"
+    s3 = "https://s3.${var.region}.io.cloud.ovh.net"
   }
 }

storage/s3-with-tf/variables.tf

@@ -0,0 +1,3 @@
+variable "region" {
+    default = "gra"
+}