Integrate awesome-prometheus-alerts vault checks

[cfi2017]

I propose to integrate the monitoring rules at https://samber.github.io/awesome-prometheus-alerts/rules#hashicorp-vault-1
into our Vault monitoring chart.

There are some checks we do not currently do with our chart.
Ideally, I'd like to point to a reference of the upstream so we don't have to maintain a carbon-copy of the monitoring rules ourselves.

Affected chart
vault-monitoring

[hairmare]

We did a similar job for cert-manager-monitoring where we provide a Helm compatible version of https://gitlab.com/uneeq-oss/cert-manager-mixin

Given that the upstream rules only get changed about once per year, I'm not sure we can find ways to warrant the additional efforts we'd need for automation. Would you have anything in mind for referencing upstream?