cmd/gerritbot: update run command in deployment config

Change-Id: Ib0c0f93ad9712025409226a5dfda097f4f4946b1
Reviewed-on: https://go-review.googlesource.com/c/build/+/176042
Reviewed-by: Brad Fitzpatrick <bradfitz@golang.org>

cmd/gerritbot/deployment-prod.yaml

@@ -16,7 +16,7 @@ spec:
       - name: gerritbot
         image: gcr.io/symbolic-datum-552/gerritbot:latest
         imagePullPolicy: Always
-        command: ["/tini", "--", "/gerritbot", "-listen=:80", "-autocert-bucket=golang-gerritbot-autocert", "-gitcookies-file=/gitcookies"]
+        command: ["/sbin/tini", "--", "/gerritbot", "-listen=:80", "-autocert-bucket=golang-gerritbot-autocert", "-gitcookies-file=/gitcookies"]
         ports:
         - containerPort: 80
         - containerPort: 443