Bump io.netty:netty-all from 4.1.115.Final to 4.1.116.Final in /mr

Bumps [io.netty:netty-all](https://github.com/netty/netty) from 4.1.115.Final to 4.1.116.Final.
- [Commits](netty/netty@netty-4.1.115.Final...netty-4.1.116.Final)

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

Signed-off-by: dependabot[bot] <[email protected]>

mr/build.gradle

@@ -63,7 +63,7 @@ dependencies {
 
     testImplementation(project(":test:shared"))
     testImplementation("com.fasterxml.jackson.core:jackson-databind:2.18.2")
-    testImplementation("io.netty:netty-all:4.1.115.Final")
+    testImplementation("io.netty:netty-all:4.1.116.Final")
     testImplementation("org.elasticsearch:securemock:1.2")
 
     itestEmbedded(project(":test:shared"))