List any issues this PR will resolve, e.g. Closes [...].
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.
For more information on following Developer Certificate of Origin and signing off your commits, please check here.
Description
Upgrade keycloak to 26.0.0. Also updates readme.
Issues Resolved
List any issues this PR will resolve, e.g. Closes [...].
By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license. For more information on following Developer Certificate of Origin and signing off your commits, please check here.