Identity-operate integration

[Zelldon]

Integrates Identity with Operate.

• uses the recent release candidate at the time (8.0.0-rc1)
• Configure Operate and Identity to communicate with each other
• Make it possible to disable this configuration
• Auto generate a secret for Operate-Identity ( can be also overwritten by user and an existing secret)
• Adjust docs, values file
• Add notes in Helm release notes file
• Add template tests
• Add integration test for operate login

New notes:

### Operate

As part of the Operate HELM Chart an ingress definition can be deployed, but you require to have an Ingress Controller for that Ingress to be Exposed.
In order to deploy the ingress manifest, set `operate.ingress.enabled` to `true`.
If you don't have an Ingress Controller you can use kubectl port-forward to access Operate from outside the cluster:

> kubectl port-forward svc/camunda-platform-test-operate 8080:80

Per default authentication via Identity/Keycloak is enabled. In order to login into Operate please port-forward to Keycloak
as well, otherwise a login will not be possible. Make sure you use `18080` as port.

> kubectl port-forward svc/camunda-platform-tes 18080:80

Now you can point your browser to `http://localhost:8080`

Default user and password: "demo/demo"

@dlavrenuek maybe you can shortly check whether the config is like we discuss ( I would expect, just to be sure)
@npepinpe please do a normal review :)

[Zelldon]

Keycloak has the weird property to cap the names at 20 chars, the reason is that wildfly only supports a certain amount of characters 🤷 😆

[npepinpe]

🚀

@dlavrenuek - I didn't really check if it's correctly configured or working properly, just that it starts. I think you will be better placed to check that it works as expected.

Other notes:

• ❓ The version is 8.0.0-rc1, I guess we'll bump this to 8.0.0 soon? Everything should be available now.
• ❓ There are 4 configuration settings for the integration, but only two of them are tested in the deployment test, and one in the secret test - any reason for not testing the last one about the root URL? Or maybe I missed it.

Anyway, no blockers that I could see

[Zelldon]

Thanks for your review @npepinpe 👍

Regarding your questions:

Other notes:

❓ The version is 8.0.0-rc1, I guess we'll bump this to 8.0.0 soon? Everything should be available now.

I will do it after I merged all PR's, otherwise we have to many conflicts.

❓ There are 4 configuration settings for the integration, but only two of them are tested in the deployment test, and one in the secret test - any reason for not testing the last one about the root URL? Or maybe I missed it.

The others are tested via golden files. In the template tests (in deployment test) we only test conditional properties.

I will merge it after @dlavrenuek gives us the go :)

[dlavrenuek]

Some small comments but not a deal breaker from my side

[Zelldon]

Thanks for your reviews I will merge this. I think we can continuously improve if we see anything.