One can't hold this SLO, it heavily depends on the size of the
downloads.

Finally got around to fix the kubelet certificate situation. This patch
resolves the outstanding issue with having this flag around.

It turned out, that pushing all warning to GitLab resulted in being too
noisy. There were more than 30 issues opened in no time, often
duplicates, due to how GitLab maps or rather doesn't map alerts in the
free version.

This reverts commit de6e02d9.

This patch enables the delivery of alerts with the severity warning to
GitLab, which allows to handle the issues without causing alert fatique.