Alerting: UI changes required to support v3 and Auth in Kafka Contact Point

[ghost]

What is this feature?

This PR adds the code required to automatically create UI elements to match changes made in this alerting PR: grafana/alerting#28

This adds UI elements to perform the following,

1. A checkbox to opt for basic auth.
2. A text field to supply the username
3. A dropdown to select a way to supply the password: The password can be entered in the UI or be supplied a file on the grafana server.
4. A dropdown to select the API version to use when publishing kafka messages.

Why do we need this feature?

1. Using this feature without auth is fine in simple projects but doesn't really work in larger companies.
2. The existing Kafka Contact Point only supported v2 APIs. While this was fine till now - newer systems are moving towards v3. Confluent is already only deploying v3 APIs for their Kafka Cloud Clusters.

Who is this feature for?

Anyone using the Kafka REST Contact Point with Grafana.

Which issue(s) does this PR fix?

Fixes #41176

Screenshots

The user can supply a password right here.

Or, they can choose to give a file path,

The user can select the desired API version like this,

References

Corresponding change in grafana/alerting: grafana/alerting#28

Need help with

1. How do I make sure that this and the corresponding alerting changes go in together? If one goes in without the other, things might break. Do I wait for the alerting change to merge and then update the go.mod file to pick a newer version of the alerting package? Or is this somehow handled automatically?

[CLAassistant]

All committers have signed the CLA.

[ghost]

Given #60655, I am assuming that the earliest release this change can only go into is 9.4. Is that correct?

[ghost]

Can someone help me add 9.4 as the milestone for this please? Doesn't look like I have the permissions to do so.

[ghost]

Post comments, final UI looks like this,

[yuri-tceretian]

@MohammadGhazanfar, I updated Grafana to import changes from your PR grafana/alerting#28.

[yuri-tceretian]

LGTM. Thanks for contributing!

[ghost]

Here's the latest UI,

[yuri-tceretian]

Tested:

• V3 mode with Kafka Rest Proxy.
• V2 mode with config created prior this change and after