fix(obj): update CICD tutorial with correct env vars MTA-6039 (scaleway#4950)

Author: SamyOubouaziz

tutorials/cicd-github-action-object-storage-sync/index.mdx

@@ -29,7 +29,7 @@ This tutorial will guide you through setting up a GitHub Action to deploy your A
 1. In your GitHub repository, navigate to the `.github/workflows` directory. If it does not exist, create it at the root of your repository.
 2. Create a new file named `deploy.yml` in the `.github/workflows` directory.
 
-## Defining the workflow
+### Define the workflow
 
 Copy and paste the following code into the `deploy.yml` file. This workflow will run on every push to the `main` branch, build your Astro website, and upload the built files to Scaleway Object Storage.
 
@@ -74,21 +74,21 @@ jobs:
         env:
           SCW_ACCESS_KEY: ${{ secrets.SCW_ACCESS_KEY }}
           SCW_SECRET_KEY: ${{ secrets.SCW_SECRET_KEY }}
-          SCW_PROJECT_ID: ${{ secrets.SCW_PROJECT_ID }}
-          SCW_ORGANIZATION_ID: ${{ secrets.SCW_ORGANIZATION_ID }}
+          SCW_DEFAULT_PROJECT_ID: ${{ secrets.SCW_DEFAULT_PROJECT_ID }}
+          SCW_DEFAULT_ORGANIZATION_ID: ${{ secrets.SCW_DEFAULT_ORGANIZATION_ID }}
 ```
 
-Configure repository secrets
+### Configure the repository secrets
 
 In your GitHub repository, go to Settings > Secrets and variables > Actions.
 Add the following secrets with your Scaleway credentials:
 
 - SCW_ACCESS_KEY
 - SCW_SECRET_KEY
-- SCW_PROJECT_ID
-- SCW_ORGANIZATION_ID
+- SCW_DEFAULT_PROJECT_ID
+- SCW_DEFAULT_ORGANIZATION_ID
 
-Commit and push your changes
+### Commit and push your changes
 
 Run the commands below to commit and push the `deploy.yml` file to your repository. If you are working directly on your main branch, this will trigger the GitHub Action to run on the main branch.