[graphite] - Add option to disable expose of the carbon UDP port

[holubovskyi]

What this PR does / why we need it:

When using the graphite chart with the service type LoadBalancer and statsd interface type TCP in the GKE the following error occurs:

Error: Service "grafana-graphite" is invalid: ...
cannot create an external load balancer with mix protocols

This error occurs because GCP doesn't allow to configure load balancer with mix of the TCP and UDP protocols.

This PR adds the ability to disable exposing of the carbon UDP port by using service.enableCarbonUdpPort value.

Checklist

[Place an '[x]' (no spaces) in all applicable fields. Please remove unrelated fields.]

• [x] DCO signed
• [x] Chart Version bumped (if the pr is an update to an existing chart)
• [x] Variables are documented in the README.md
• [x] Title of the PR starts with chart name (e.g. [fluentd-elasticsearch])

[monotek]

Please also sign your commits to fix the dco check

[stale[bot]]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs. Thank you for your contributions.