SONAR-14397 Update the Java < 11 warning displayed by SonarQube Scanners

sonar-scanner-engine/src/main/java/org/sonar/scanner/bootstrap/GlobalContainer.java

@@ -85,7 +85,7 @@ public class GlobalContainer extends ComponentContainer {
     try {
       String.class.getMethod("isBlank");
     } catch (NoSuchMethodException e) {
-      LOG.warn("SonarScanner will require Java 11 to run starting in SonarQube 8.x");
+      LOG.warn("SonarScanner will require Java 11 to run starting in SonarQube 9.x");
     }
   }