30 issues per run on stale bot

Now that we use a fixed branch for the bot, and since I removed all the untagged stale issues we can go back to full thrust
https://github.com/nextcloud/server/issues?page=1&q=is%3Aissue+sort%3Aupdated-desc+is%3Aopen+label%3Astale+-label%3A%22needs+info%22+-label%3A%220.+Needs+triage%22+-label%3A%221.+to+develop%22+-label%3A%223.+to+review%22&utf8=%E2%9C%93