Update Keycloak Hosting Integration to work with Azure Container Apps

[anderly]

Description

Per #6004, deploying a container provisioned via the Keycloak integration won't start in Azure Container Apps (ACA).

ACA will try to activate it, but it continuously fails.

The container reports this in the logs:

Key material not provided to setup HTTPS. Please configure your keys/certificates or start the server in development mode.

This PR includes a basic starting point for changes required to get Keycloak working in Azure Container Apps (see #6004).

This may need to be altered to add local dev case to continue to use default local dev port of 8080 via http and only include these additional env vars when deploying to azure container apps or if passed port is 8443. Open to making additional changes based on review and suggestions, but wanted to show bare minimum to get it working and be able to support ACA SSL.

Fixes # 6004

Checklist

• Is this feature complete?
  • Yes. Ready to ship.
  • No. Follow-up changes expected.
• Are you including unit tests for the changes and scenario tests if relevant?
  • Yes
  • No
• Did you add public API?
  • Yes
    • If yes, did you have an API Review for it?
      • Yes
      • No
    • Did you add <remarks /> and <code /> elements on your triple slash comments?
      • Yes
      • No
  • No
• Does the change make any security assumptions or guarantees?
  • Yes
    • If yes, have you done a threat model and had a security review?
      • Yes
      • No
  • No
• Does the change require an update in our Aspire docs?
  • [] Yes
    • Is this introducing a breaking change?
      • Yes
        • Link to aspire-docs issue (please use this breaking-change template):
      • No
        • Link to aspire-docs issue (please use this doc-idea template):
  • No