docs(account_project): add example with provider configuration (#2333)

Author: Codelax

docs/resources/account_project.md

@@ -7,14 +7,41 @@ page_title: "Scaleway: scaleway_account_project"
 
 Manages organization's projects on Scaleway.
 
-## Example Usage
+## Examples
+
+### Basic
 
 ```hcl
 resource "scaleway_account_project" "project" {
   name = "project"
 }
 ```
 
+### Use project in provider configuration
+
+If you want to use as default a project created in terraform you can use a temporary provider alias.
+This project can then be used to configure your default provider.
+
+```hcl
+provider "scaleway" {
+  alias = "tmp"
+}
+
+resource scaleway_account_project "project" {
+  provider = scaleway.tmp
+  name = "my_project"
+}
+
+provider "scaleway" {
+  project_id = scaleway_account_project.project.id
+}
+
+resource "scaleway_instance_server" "server" { // Will use scaleway_account_project.project
+  image = "ubuntu_jammy"
+  type  = "PRO2-XXS"
+}
+```
+
 ## Arguments Reference
 
 The following arguments are supported: