chore(samples): remove unnecessary permission (#315)

Co-authored-by: Anthonios Partheniou <[email protected]>

Author: kchertenko

generated_samples/interactive-tutorials/README.md

@@ -78,7 +78,7 @@ To access the Retail API, you must create a service account. Check that you are
 1. Assign the needed roles to your service account:
 
     ```bash
-    for role in {retail.admin,storage.admin,bigquery.admin}
+    for role in {retail.admin,storage.admin}
     do gcloud projects add-iam-policy-binding <YOUR_PROJECT_ID> --member="serviceAccount:<YOUR_SERVICE_ACCOUNT_ID>@<YOUR_PROJECT_ID>.iam.gserviceaccount.com" --role="roles/${role}"
     done
     ```

generated_samples/interactive-tutorials/user_environment_setup.sh

@@ -29,7 +29,7 @@
   gcloud iam service-accounts create "$service_account_id"
 } && {
   # assign necessary roles to your new service account
-  for role in {retail.admin,editor,bigquery.admin}
+  for role in {retail.admin,editor}
     do
       gcloud projects add-iam-policy-binding "$project_id" --member="serviceAccount:$service_account_id@$project_id.iam.gserviceaccount.com" --role=roles/"${role}"
   done