Reapply "Upgrade to Netty 4.2.15.Final"

This reverts commit 490614f.

Closes gh-50692

Author: wilkinsona

module/spring-boot-r2dbc/build.gradle

@@ -90,3 +90,9 @@ tasks.named("compileTestJava") {
 tasks.named("compileDockerTestJava") {
 	options.nullability.checking = "tests"
 }
+
+tasks.named("dockerTest") {
+	systemProperties = [
+		"io.netty.handler.ssl.defaultEndpointVerificationAlgorithm" : "NONE"
+	]
+}

platform/spring-boot-dependencies/build.gradle

@@ -1693,7 +1693,7 @@ bom {
 			releaseNotes("https://github.com/neo4j/neo4j-java-driver/releases/tag/{version}")
 		}
 	}
-	library("Netty", "4.2.14.Final") {
+	library("Netty", "4.2.15.Final") {
 		prohibit {
 			contains ".Alpha"
 			contains ".Beta"