CLDC-2690: Update s3 service to use ECS credential provider when not on PaaS

app/services/storage/s3_service.rb

@@ -54,11 +54,11 @@ module Storage
     end
 
     def create_client
-      credentials =
+      credentials = PlatformHelper.is_paas? ?
         Aws::Credentials.new(
           @configuration.access_key_id,
           @configuration.secret_access_key,
-        )
+        ) : Aws::ECSCredentials.new
       Aws::S3::Client.new(
         region: @configuration.region,
         credentials:,