Pass -XX:TieredStopAtLevel=1 for tests to reduce flakiness (#102)

diff --git a/buildSrc/src/main/groovy/pulsar-client-reactive.test-conventions.gradle b/buildSrc/src/main/groovy/pulsar-client-reactive.test-conventions.gradle
index 91c064e..37cbc80 100644
--- a/buildSrc/src/main/groovy/pulsar-client-reactive.test-conventions.gradle
+++ b/buildSrc/src/main/groovy/pulsar-client-reactive.test-conventions.gradle
@@ -49,4 +49,11 @@
 	shouldRunAfter test
 }
 
-check.dependsOn integrationTest
\ No newline at end of file
+check.dependsOn integrationTest
+
+
+tasks.withType(Test) {
+	// reduces CPU usage in tests when JIT compiler doesn't spend time compiling code
+	// this could help reduce flakiness in CI where there's less CPU resources available
+	jvmArgs '-XX:TieredStopAtLevel=1'
+}
\ No newline at end of file