feat: add helm configcat-proxy helm chart

[mariot8]

Describe the purpose of your pull request

• Provide a clear and concise description of the changes.
  Add configcat-proxy helm chart and release pipeline

Related issues (only if applicable)

• Provide links to issues relating to this pull request.
  Add Helm Chart to Deploy ConfigCat Proxy to Kubernetes #31

How to test? (only if applicable)

• What part of the application was affected by the changes? What should be tested?
  helm install chart and see if the pods are running

Security (only if applicable)

• Describe any potential risks that could affect the component in terms of security.

Requirement checklist (only if applicable)

• I have covered the applied changes with automated tests.
• I have executed the full automated test set against my changes.
• I have validated my changes against all supported platform versions.
• I have read and accepted the contribution agreement.

[z4kn4fein]

Hey @mariot8, thank you for the contribution! We'll review and test your PR soon

[z4kn4fein]

Hey @mariot8, I finally had the chance to try the chart out. Overall, it's working great, thank you! I have some minor suggestions, could you please check them? Thanks!

[mariot8]

Thank you for the review. These are small change requests, but I’ll be able to address them next week.

[mariot8]

I know this may not be ideal yet - cache backends other than Redis are still missing, etc.
But I hope the community or ConfigCat will turn it into a gem.

[z4kn4fein]

I think it's a good start, so I'm going to merge this. Later, I'll add support for the new proxy profiles and see how it goes. :)
Thank you again for your contribution!