fix: fix keycloak url in play docs

[huygur]

Description

With this recent change in the camunda-platform repository, the keycloak port in docker-compose files were updated: camunda/camunda-platform#806

This affected Play Self Managed example values. Which is what this PR aims to fix.

⚠️ I can see that keycloak:8080 is mentioned in a couple more places in our docs, which might also need to be updated, but I don't have enough time to check all of these, nor the confidence to confirm they need to be updated. It might worth to double-check with the respective teams.

When should this change go live?

• This is a bug fix, security concern, or something that needs urgent release support.
• This is already available but undocumented and should be released within a week.
• This on a specific schedule and the assignee will coordinate a release with the DevEx team. (apply hold label or convert to draft PR)
• This is part of a scheduled alpha or minor. (apply alpha or minor label)
• There is no urgency with this change and can be released at any time.

PR Checklist

• My changes are for an already released minor and are in /versioned_docs directory.
• My changes are for the next minor and are in /docs directory (aka /next/).

• My changes require an Engineering review, and I've assigned the Engineering DRI or delegate.
• My changes require a technical writer review, and I've assigned @camunda/tech-writers as a reviewer.

[github-actions]

👋 🤖 🤔 Hello! Did you make your changes in all the right places?

These files were changed only in docs/. You might want to duplicate these changes in versioned_docs/version-8.5/.

• docs/components/modeler/web-modeler/play-your-process.md

You may have done this intentionally, but we wanted to point it out in case you didn't. You can read more about the versioning within our docs in our documentation guidelines.

[conceptualshark]

Thank you for this catch. 👍 I've created #4271 to follow up on other instances of the old keycloak port.

[huygur]

@conceptualshark thanks! this is failing: https://github.com/camunda/camunda-docs/actions/runs/10770289039/job/29863335539?pr=4269 is this important or can I merge the PR?

[conceptualshark]

@huygur No need to resolve that if everything else is passing! It's an internal devex workflow.