Bump netty-all from 4.1.89.Final to 4.1.91.Final in /keycloak-plugins

Bumps [netty-all](https://github.com/netty/netty) from 4.1.89.Final to 4.1.91.Final.
- [Release notes](https://github.com/netty/netty/releases)
- [Commits](netty/netty@netty-4.1.89.Final...netty-4.1.91.Final)

---
updated-dependencies:
- dependency-name: io.netty:netty-all
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

keycloak-plugins/radius-plugin/pom.xml

@@ -52,7 +52,7 @@
         <dependency>
             <groupId>io.netty</groupId>
             <artifactId>netty-all</artifactId>
-            <version>4.1.89.Final</version>
+            <version>4.1.91.Final</version>
             <scope>provided</scope>
         </dependency>
         <dependency>