feat(metrics): add prometheus rules (and update exporter)

[wrenix]

Description of the change

Benefits

Possible drawbacks

Applicable issues

• fixes #

Additional information

Checklist

• [x] I have read the CONTRIBUTING.md doc.
• [x] DCO has been signed off on the commit.
• [x] Chart version bumped in Chart.yaml according to semver.
• [ ] (optional) Parameters are documented in the README.md

[wrenix]

such small thinks, make me happy:

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PS: Hope #574 comes fast, that we track the exporter image better ;)

[wrenix]

merged with #673