[deploy-sourcegraph] Increase default CPU limits

Created by: keegancsmith

I noticed kubernetes-slack-bot was failing to do an HTTPs request due to timeout. It was due to the CPU limit being set to 10m. IE 10m is so low a simple go program can't do an HTTPs request without a timeout. I then noticed we use this value a lot in this repo, even for large programs like redis or Postgres. We should probably use a more appropriate value.