Update samples dependency from JUnit 4.11 to 4.12.

Author: garydgregory

log4j-samples/pom.xml

@@ -72,7 +72,7 @@
       <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
-        <version>4.11</version>
+        <version>4.12</version>
         <scope>test</scope>
       </dependency>
     </dependencies>