Update jUnit version to 4.12

Motivation:

Too many new features in the new release of jUnit.
https://github.com/junit-team/junit/blob/master/doc/ReleaseNotes4.12.md

Modifications:

- Changed version of jUnit from 4.11 to 4.12 in the parent pom.

Result:

Allows using new testing features.

pom.xml

@@ -649,7 +649,7 @@
       <dependency>
         <groupId>junit</groupId>
         <artifactId>junit</artifactId>
-        <version>4.11</version>
+        <version>4.12</version>
         <scope>test</scope>
       </dependency>
       <dependency>