Bump io.netty:netty-bom from 4.1.104.Final to 4.1.106.Final (#389)

Bumps [io.netty:netty-bom](https://github.com/netty/netty) from 4.1.104.Final to 4.1.106.Final.
- [Commits](netty/netty@netty-4.1.104.Final...netty-4.1.106.Final)

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

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

acceptance-tests/build.gradle.kts

@@ -34,7 +34,7 @@ dependencies {
 
     implementation("org.jenkins-ci:acceptance-test-harness:5740.vd30f30408987")
 
-    testImplementation(platform("io.netty:netty-bom:4.1.104.Final"))
+    testImplementation(platform("io.netty:netty-bom:4.1.106.Final"))
     testImplementation("io.ratpack:ratpack-test:2.0.0-rc-1")
 
     add(gradlePlugin.name, project(path = ":", configuration = "gradlePluginJpi"))