Fix invalid PromQL query in the Cilium Metrics Grafana dashboard

[mikemykhaylov]

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The existing query for the Policies per Node chart in the Cilium Metrics dashboard in the monitoring-example.yaml contained invalid PromQL. Additionally, the correct value to be filtered on is "failure", not "fail".

Fix PromQL query in Cilium Metrics dashboard

[maintainer-s-little-helper]

Commit ab0dca3 does not match "(?m)^Signed-off-by:".

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[joamaki]

Looks good, but please remove the merge commit.

[mikemykhaylov]

Should be good now

[aanm]

/test

[joamaki]

/test

[julianwiedmann]

/test

[julianwiedmann]

Added backport labels, sounds like this is essentially a docs bug.