Upgrade to Netty 4.1.52

Author: rstoyanchev

build.gradle

@@ -25,7 +25,7 @@ configure(allprojects) { project ->
 	dependencyManagement {
 		imports {
 			mavenBom "com.fasterxml.jackson:jackson-bom:2.11.2"
-			mavenBom "io.netty:netty-bom:4.1.51.Final"
+			mavenBom "io.netty:netty-bom:4.1.52.Final"
 			mavenBom "io.projectreactor:reactor-bom:2020.0.0-RC1"
 			mavenBom "io.r2dbc:r2dbc-bom:Arabba-SR7"
 			mavenBom "io.rsocket:rsocket-bom:1.1.0-M2"