terraform: add Cloud Build trigger to deploy on push

Change-Id: I63f2676c3eca7fae79ef86c8f3e10fcd3e919ce3
Reviewed-on: https://go-review.googlesource.com/c/pkgsite-metrics/+/469215
Run-TryBot: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Zvonimir Pavlinovic <zpavlinovic@google.com>
diff --git a/terraform/main.tf b/terraform/main.tf
index a008bfe..b4ca55a 100644
--- a/terraform/main.tf
+++ b/terraform/main.tf
@@ -194,6 +194,20 @@
 
 }
 
+# Cloud Build trigger to deploy the prod worker on every push to master.
+resource "google_cloudbuild_trigger" "deploy_prod_worker" {
+  name = "Deploy-Prod-Ecosystem-Worker"
+  trigger_template {
+    branch_name = "master"
+    repo_name   = "pkgsite-metrics"
+  }
+  filename = "deploy/worker.yaml"
+
+  substitutions = {
+    "_ENV"        = "prod"
+    "_BQ_DATASET" = "test_prod"
+  }
+}
 
 # Deployment environments