Change thanos-compact crashloop alert to create an issue instead of paging

Igorrequested to merge
thanos-crashloop-incident-issue into master

We're getting frequent pages for thanos-compact: https://gitlab.com/gitlab-com/gl-infra/reliability/-/issues/17298.

This MR changes those pages to create an incident issue instead of paging the on-call. This way, we don't need to deal with it over the weekend, it can be addressed the following Monday.

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