Parameterize service.protocol for opensearch-dashboards

[enes-zed]

Description

This will allow users to specify the protocol for the service definition, which is currently hardcoded to TCP. Allows for better integration e.g. with Istio.

Issues Resolved

https://github.com/opensearch-project/helm-charts/issues/532

Check List

• [ ] Commits are signed per the DCO using --signoff

For any changes to files within Helm chart directories:

• [ ] Helm chart version bumped
• [ ] Helm chart CHANGELOG.md updated to reflect change

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license. For more information on following Developer Certificate of Origin and signing off your commits, please check here.

[TheAlgo]

@prudhvigodithi Can you also take a look at this PR?

[prudhvigodithi]

Hey @enes-zed the LGTM, thanks for your contribution, can you please update the chart README.md, CHANGELOG.md and Chart.yaml, here is the sample merged PR https://github.com/opensearch-project/helm-charts/pull/530/files. Also do you think this change is useful for opensearch chart as well? Thank you @getsaurabh02

[TheAlgo]

@enes-zed any update on the PR?