Upgrade to Reactor Dysprosium-RELEASE

Closes gh-23695

build.gradle

@@ -45,7 +45,7 @@ configure(allprojects) { project ->
 		imports {
 			mavenBom "com.fasterxml.jackson:jackson-bom:2.9.9"
 			mavenBom "io.netty:netty-bom:4.1.39.Final"
-			mavenBom "io.projectreactor:reactor-bom:Dysprosium-BUILD-SNAPSHOT"
+			mavenBom "io.projectreactor:reactor-bom:Dysprosium-RELEASE"
 			mavenBom "org.eclipse.jetty:jetty-bom:9.4.20.v20190813"
 			mavenBom "org.jetbrains.kotlin:kotlin-bom:1.3.50"
 			mavenBom "org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.3.1"
@@ -299,8 +299,6 @@ configure(allprojects) { project ->
 		repositories {
 			mavenCentral()
 			maven { url "https://repo.spring.io/libs-spring-framework-build" }
-			maven { url "https://repo.spring.io/milestone" } // Reactor
-			maven { url "https://repo.spring.io/snapshot" } // Reactor
 		}
 	}
 	configurations.all {