add gitserver startup probe

Author: camdencheek

charts/sourcegraph/templates/gitserver/gitserver.StatefulSet.yaml

@@ -56,6 +56,14 @@ spec:
         {{- end }}
         {{- include "sourcegraph.openTelemetryEnv" . | nindent 8 }}
         terminationMessagePolicy: FallbackToLogsOnError
+        # Temporary: when migrating from repo names to repo IDs on disk,
+        # gitserver can take a little while to start up. To avoid killing the
+        # pod because of a failed liveness probe, we give it 2 minutes to start up.
+        startupProbe:
+          tcpSocket:
+            port: rpc
+          failureThreshold: 120
+          periodSeconds: 1
         livenessProbe:
           initialDelaySeconds: 5
           tcpSocket: