Clean up JUnit deps (jenkins-infra#276)

pom.xml

@@ -32,8 +32,6 @@
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
         <!-- Dependency versions -->
-        <groovy.version>3.0.9</groovy.version>
-        <junit.version>5.8.2</junit.version>
         <jenkins-pipeline-unit.version>1.13</jenkins-pipeline-unit.version>
         <groovy-eclipse-compiler.version>3.7.0</groovy-eclipse-compiler.version>
     </properties>
@@ -42,21 +40,25 @@
         <dependency>
             <groupId>org.codehaus.groovy</groupId>
             <artifactId>groovy-all</artifactId>
-            <version>${groovy.version}</version>
+            <version>3.0.9</version>
             <!-- Type pom replaces the über "groovy-all.jar", for version 3+ -->
             <type>pom</type>
             <scope>test</scope>
+            <exclusions>
+                <exclusion>
+                    <groupId>org.codehaus.groovy</groupId>
+                    <artifactId>groovy-test-junit5</artifactId>
+                </exclusion>
+                <exclusion>
+                    <groupId>org.codehaus.groovy</groupId>
+                    <artifactId>groovy-testng</artifactId>
+                </exclusion>
+            </exclusions>
         </dependency>
         <dependency>
-            <groupId>org.junit.jupiter</groupId>
-            <artifactId>junit-jupiter-api</artifactId>
-            <version>${junit.version}</version>
-            <scope>test</scope>
-        </dependency>
-        <dependency>
-            <groupId>org.junit.vintage</groupId>
-            <artifactId>junit-vintage-engine</artifactId>
-            <version>${junit.version}</version>
+            <groupId>junit</groupId>
+            <artifactId>junit</artifactId>
+            <version>4.13.2</version>
             <scope>test</scope>
         </dependency>
         <dependency>