docs(srv): update doc on testing resource

Author: SamyOubouaziz

pages/serverless-containers/how-to/test-a-container.mdx

@@ -11,10 +11,6 @@ import Requirements from '@macros/iam/requirements.mdx'
 
 This page shows you how to execute Serverless Containers from the [Scaleway console](https://console.scaleway.com). The **Test** feature of a container allows you to run your code using a selection of methods to make sure it behaves as expected.
 
-<Message type="note">
-Testing **Private** Serverless Functions is not possible using the Scaleway console due to CORS limitations. Refer to the [dedicated documentation](/serverless-containers/how-to/create-auth-token-from-console/) for more information on how to secure and test a private function.
-</Message>
-
 <Requirements />
 
 - A Scaleway account logged into the [console](https://console.scaleway.com)
@@ -37,6 +33,15 @@ Testing **Private** Serverless Functions is not possible using the Scaleway cons
 
 8. Copy the generated command, then execute it in a terminal.
 
+    <Message type="note">
+    Testing a private container requires you use an [authentication token](/serverless-containers/how-to/create-auth-token-from-console/) as a header, as shown below:
+
+    ```bash
+    export $TOKEN=<YOUR_AUTH_TOKEN>
+    curl -H "X-Auth-Token: $TOKEN" \ <YOUR_FUNCTION_ENDPOINT>
+    ````
+    </Message>
+
 The output of your terminal displays the response from your container, and the status code.
 
 <Message type="note">

pages/serverless-containers/troubleshooting/tests-fail-on-container.mdx

@@ -21,5 +21,6 @@ I get error messages when testing Serverless Containers using the Scaleway Conso
 
 - Make sure you have created an [authentication token](/serverless-containers/how-to/create-auth-token-from-console/) for your private function, then execute a `curl` request from a terminal, as shown below:
     ```bash
-    curl -H "X-Auth-Token: <YOUR_AUTH_TOKEN>" \ <YOUR_CONTAINER_ENDPOINT>
+    export $TOKEN=<YOUR_AUTH_TOKEN>
+    curl -H "X-Auth-Token: $TOKEN" \ <YOUR_CONTAINER_ENDPOINT>
     ```

pages/serverless-functions/how-to/test-a-function.mdx

@@ -11,10 +11,6 @@ import Requirements from '@macros/iam/requirements.mdx'
 
 This page shows you how to execute Serverless Functions from the [Scaleway console](https://console.scaleway.com). The **Test** feature of a function allows you to run your code using a selection of methods to make sure it behaves as expected.
 
-<Message type="note">
-Testing **Private** Serverless Functions is not possible using the Scaleway console due to CORS limitations. Refer to the [dedicated documentation](/serverless-functions/how-to/create-auth-token-from-console/) for more information on how to secure and test a private function.
-</Message>
-
 <Requirements />
 
 - A Scaleway account logged into the [console](https://console.scaleway.com)
@@ -37,9 +33,16 @@ Testing **Private** Serverless Functions is not possible using the Scaleway cons
 
 8. Copy the generated command, then execute it in a terminal.
 
-The output of your terminal displays the response from your function, and the status code.
+    <Message type="note">
+    Testing a private function requires you use an [authentication token](/serverless-functions/how-to/create-auth-token-from-console/) as a header, as shown below:
 
-The **Output** section displays the response from your function and the status code.
+    ```bash
+    export $TOKEN=<YOUR_AUTH_TOKEN>
+    curl -H "X-Auth-Token: $TOKEN" \ <YOUR_FUNCTION_ENDPOINT>
+    ````
+    </Message>
+
+The output of your terminal displays the response from your function, and the status code.
 
 <Message type="note">
 If you encounter a message error while testing your function, refer to the [dedicated troubleshooting](/serverless-functions/troubleshooting/tests-fail-on-function/) for more information.

pages/serverless-functions/troubleshooting/tests-fail-on-function.mdx

@@ -21,5 +21,6 @@ I get error messages when testing Serverless Functions using the Scaleway Consol
 
 - Make sure you have created an [authentication token](/serverless-functions/how-to/create-auth-token-from-console/) for your private function, then execute a `curl` request from a terminal, as shown below:
     ```bash
-    curl -H "X-Auth-Token: <YOUR_AUTH_TOKEN>" \ <YOUR_FUNCTION_ENDPOINT>
+    export $TOKEN=<YOUR_AUTH_TOKEN>
+    curl -H "X-Auth-Token: $TOKEN" \ <YOUR_FUNCTION_ENDPOINT>
     ```