update a couple of test dependencies

Closes #17

Author: elharo

pom.xml

@@ -362,13 +362,13 @@ under the License.
     <dependency>
       <groupId>junit</groupId>
       <artifactId>junit</artifactId>
-      <version>4.12</version>
+      <version>4.13</version>
       <scope>test</scope>
     </dependency>
     <dependency>
       <groupId>org.mockito</groupId>
       <artifactId>mockito-core</artifactId>
-      <version>2.19.0</version>
+      <version>2.28.2</version>
       <scope>test</scope>
     </dependency>
     <dependency>