compile before push I should

Author: SylvainJuge

javaagent-tooling/javaagent-tooling-java9/src/main/java/io/opentelemetry/javaagent/tooling/ModuleOpener.java

@@ -19,6 +19,7 @@
 import net.bytebuddy.description.type.PackageDescription;
 import net.bytebuddy.dynamic.loading.ClassInjector;
 import net.bytebuddy.utility.JavaModule;
+import javax.annotation.Nullable;
 
 /**
  * Module opener provides ability to open JPMS modules and allows instrumentation classloader to