Update to Reactor 2020.0.3

Closes gh-230

gradle/dependency-management.gradle

@@ -7,7 +7,7 @@ if (!project.hasProperty("springSecurityVersion")) {
 }
 
 if (!project.hasProperty("reactorVersion")) {
-	ext.reactorVersion = "2020.0.+"
+	ext.reactorVersion = "2020.0.3"
 }
 
 if (!project.hasProperty("locksDisabled")) {