Specifiy java compiler version correctly

Change-Id: Iffc764cc7ea5bd55ae89e478898d0ad76617d24b
diff --git a/pom.xml b/pom.xml
index b9cffac..1ff8f9b 100644
--- a/pom.xml
+++ b/pom.xml
@@ -11,8 +11,6 @@
     <properties>
         <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
         <jackson.version>[2.10.3,)</jackson.version>
-        <maven.compiler.target>1.8</maven.compiler.target>
-        <maven.compiler.source>1.8</maven.compiler.source>
     </properties>
 
     <build>
@@ -108,6 +106,8 @@
                 <artifactId>maven-compiler-plugin</artifactId>
                 <version>3.8.1</version>
                 <configuration>
+                    <source>1.8</source>
+                    <target>1.8</target>
                     <showDeprecation>true</showDeprecation>
                     <annotationProcessorPaths>
                         <path>