perf: extend ingress timeout

Cloud Scheduler calls /cron/syncinflux hourly. If there are several days
of results (because we deleted data and want to re-sync), then this can
take several minutes to complete. Allow longer connections.

Change-Id: I334b86b91e6e0ebe640a7a05afd04f1193c092f6
Reviewed-on: https://go-review.googlesource.com/c/build/+/623999
Reviewed-by: Michael Knyszek <[email protected]>
LUCI-TryBot-Result: Go LUCI <[email protected]>
Reviewed-by: Carlos Amedee <[email protected]>

Author: prattmic

perf/deployment-prod.yaml

@@ -57,6 +57,7 @@ metadata:
   namespace: prod
   name: perf-internal
   annotations:
+    cloud.google.com/backend-config: '{"default": "build-ingress-perf-backend"}'
     cloud.google.com/neg: '{"ingress": false}'
     cloud.google.com/app-protocols: '{"https":"HTTP2"}'
 spec:
@@ -67,3 +68,11 @@ spec:
   selector:
     app: perf
   type: NodePort
+---
+apiVersion: cloud.google.com/v1
+kind: BackendConfig
+metadata:
+  namespace: prod
+  name: build-ingress-perf-backend
+spec:
+  timeoutSec: 3600  # For long calls to /cron/syncinflux.