Fix installation process (#83)

* Update generate-tf-backend.sh

* Update README.md

infrastructure/terraform/README.md

@@ -75,6 +75,7 @@ Step by step installation guide with [![Open in Cloud Shell](https://gstatic.com
 
 1. Authenticate with additional OAuth 2.0 scopes needed to use the Google Analytics Admin API:
    ```shell
+   gcloud auth login
    gcloud auth application-default login --quiet --scopes="openid,https://www.googleapis.com/auth/userinfo.email,https://www.googleapis.com/auth/cloud-platform,https://www.googleapis.com/auth/sqlservice.login,https://www.googleapis.com/auth/analytics,https://www.googleapis.com/auth/analytics.edit,https://www.googleapis.com/auth/analytics.provision,https://www.googleapis.com/auth/analytics.readonly,https://www.googleapis.com/auth/accounts.reauth"
    ```
 

scripts/generate-tf-backend.sh

@@ -47,8 +47,10 @@ section_open  "Check and set the TF_STATE_BUCKET variable"
     set_environment_variable_if_not_set "TF_STATE_BUCKET" "${TF_STATE_PROJECT}-terraform-state"
 section_close
 
-section_open "Enable the Cloud Resource Manager API with"
+section_open "Enable the Cloud Resource Manager, Service Usage and IAM APIs"
     gcloud services enable cloudresourcemanager.googleapis.com
+    gcloud services enable serviceusage.googleapis.com
+    gcloud services enable iam.googleapis.com
 section_close
 
 section_open "Creating a new Google Cloud Storage bucket to store the Terraform state in ${TF_STATE_PROJECT} project, bucket: ${TF_STATE_BUCKET}"
@@ -67,4 +69,4 @@ section_close
 
 printf "$DIVIDER"
 printf "You got the end the of your generate-tf-backend script with everything working. \n"
-printf "$DIVIDER"
+printf "$DIVIDER"