Fix missing is node active check on new metrics

[MakMuftic]

Add check if the node is active before trying to add it to active nodes inside metrics handler

PR Checklist

• I have run linter localy
• I have run unit and integration tests locally
• Rebased to master branch / merged master
• Updated CHANGELOG.md

Changes

• Add IsNodeActive function to node repo
• Add check if the node is active before trying to add it to active nodes inside metrics handler

Issues

Closes #101