[chore][receiver/kubeletstats] Add ChrsMark to kubeletstats codeowners

[ChrsMark]

Description:

Having recently been working with the kubeletstats receiver (using it and contributing to it), I would like to volunteer to help with its maintainance by intending to dedicate time to contribute to the component as well as help with the existing and future issue queue.

Also being a member of the semconv-k8s-approvers and semconv-container-approvers will help to bring more alignment between the Semantic Conventions and the Collector's implementation within this specific scope.

• ✅ Being a member of Opentelemetry organization
• PRs authored: https://github.com/open-telemetry/opentelemetry-collector-contrib/pulls?q=is%3Apr+author%3AChrsMark++label%3Areceiver%2Fkubeletstats%2Cinternal%2Fkubeletstats%2Cinternal%2Fkubelet
• Issues have been involved: https://github.com/open-telemetry/opentelemetry-collector-contrib/issues?q=is%3Aissue+commenter%3AChrsMark+label%3Areceiver%2Fkubeletstats%2Cinternal%2Fkubeletstats+

/cc @dmitryax @TylerHelmuth with whom I have already discussed about it

Link to tracking Issue: ~

Testing: ~

Documentation: ~