Upgrade to JUnit 5.7 RC1 (and RxJava 3.0.6)

See gh-25527

build.gradle

@@ -31,7 +31,7 @@ configure(allprojects) { project ->
 			mavenBom "org.eclipse.jetty:jetty-bom:9.4.31.v20200723"
 			mavenBom "org.jetbrains.kotlin:kotlin-bom:1.4.0"
 			mavenBom "org.jetbrains.kotlinx:kotlinx-coroutines-bom:1.3.9"
-			mavenBom "org.junit:junit-bom:5.6.2"
+			mavenBom "org.junit:junit-bom:5.7.0-RC1"
 		}
 		dependencies {
 			dependencySet(group: 'org.apache.logging.log4j', version: '2.13.3') {
@@ -62,7 +62,7 @@ configure(allprojects) { project ->
 			dependency "io.reactivex:rxjava:1.3.8"
 			dependency "io.reactivex:rxjava-reactive-streams:1.2.1"
 			dependency "io.reactivex.rxjava2:rxjava:2.2.19"
-			dependency "io.reactivex.rxjava3:rxjava:3.0.5"
+			dependency "io.reactivex.rxjava3:rxjava:3.0.6"
 			dependency "io.projectreactor.tools:blockhound:1.0.2.RELEASE"
 
 			dependency "com.caucho:hessian:4.0.63"