Fixed pom.xml: JUnit 4 & 5 Integration

pom.xml

@@ -1,5 +1,6 @@
 <?xml version="1.0" encoding="UTF-8"?>
-<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+  xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
   <modelVersion>4.0.0</modelVersion>
   <groupId>de.hs-fulda</groupId>
   <artifactId>TIMS</artifactId>
@@ -9,12 +10,13 @@
   <url>http://maven.apache.org</url>
   <properties>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-    <maven.compiler.target>11</maven.compiler.target>
-    <maven.compiler.source>11</maven.compiler.source>
-    <junit.jupiter.version>5.8.1</junit.jupiter.version>
+    <maven.compiler.target>1.8</maven.compiler.target>
+    <maven.compiler.source>1.8</maven.compiler.source>
+    <junit.jupiter.version>5.8.0</junit.jupiter.version>
     <junit.platform.version>1.8.1</junit.platform.version>
     <assertj.version>3.21.0</assertj.version>
-    <junit.version>3.8.1</junit.version>
+    <junit.version>4.12</junit.version>
+    <junit-vintage-engine>4.12.1</junit-vintage-engine>
     <mockito.core.version>4.1.0</mockito.core.version>
     <mockito.junit.jupiter.version>4.1.0</mockito.junit.jupiter.version>
     <junit.platform.surefire.provider.version>1.0.1</junit.platform.surefire.provider.version>
@@ -33,6 +35,11 @@
       <version>${junit.jupiter.version}</version>
       <scope>test</scope>
     </dependency>
+    <dependency>
+      <groupId>org.junit.vintage</groupId>
+      <artifactId>junit-vintage-engine</artifactId>
+      <version>${junit.jupiter.version}</version>
+    </dependency>
     <dependency>
       <groupId>org.junit.jupiter</groupId>
       <artifactId>junit-jupiter-params</artifactId>
@@ -70,6 +77,11 @@
             <artifactId>junit-platform-surefire-provider</artifactId>
             <version>${junit.platform.surefire.provider.version}</version>
           </dependency>
+          <dependency>
+            <groupId>org.junit.vintage</groupId>
+            <artifactId>junit-vintage-engine</artifactId>
+            <version>${junit-vintage-engine}</version>
+          </dependency>
           <dependency>
             <groupId>org.junit.jupiter</groupId>
             <artifactId>junit-jupiter-engine</artifactId>