[CI] Add Liveness Probe to Buildbot Container

This will automatically restart the container if the buildbot worker does
not start properly.

Fixes #571.

Author: boomanaiden154

premerge/buildbot/liveness.sh

@@ -1 +1,2 @@
+#!/bin/bash
 ps aux | grep "[b]uildbot-worker start"

premerge/buildbot_deployment.yaml

@@ -35,3 +35,9 @@ spec:
           limits:
             memory: "1Gi"
             cpu: "750m"
+        livenessProbe:
+          exec:
+            command:
+              - /liveness.sh
+            initialDelaySeconds: 10
+            periodSeconds: 60