feat(lifecycle-operator): add namespace to deploymentduration metrics

[pimmerks]

Description

This PR adds namespace attributes to both keptn_app_deploymentduration and keptn_deployment_deploymentduration metrics.

All other DORA specific metrics include either the keptn_deployment_app_namespace or the keptn_deployment_workload_namespace, except for the _deploymentduration. This PR fixes that.

This is useful for our usecase where we want to filter deploymentduration per namespace instead of per app.

How to test

Unit tests have been updated, manual verification was done to check if these namespace attributes are present on the exported metrics at localhost:2222/metrics.

Checklist

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  into multiple PRs)
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[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
No data about Duplication

See analysis details on SonarCloud

[odubajDT]

Thank you for your contribution!