Bump org.keycloak:keycloak-server-spi-private from 26.5.0 to 26.5.6 (#28)

Bumps [org.keycloak:keycloak-server-spi-private](https://github.com/keycloak/keycloak) from 26.5.0 to 26.5.6.
- [Release notes](https://github.com/keycloak/keycloak/releases)
- [Commits](https://github.com/keycloak/keycloak/compare/26.5.0...26.5.6

)

---
updated-dependencies:
- dependency-name: org.keycloak:keycloak-server-spi-private
  dependency-version: 26.5.6
  dependency-type: direct:production
...

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