Remove deprecated maven compiler version

Change-Id: I458a881f863025b12aec3a8b742e65617de05d17
Reviewed-on: https://korap.ids-mannheim.de/gerrit/c/KorAP/Koral/+/9104
Reviewed-by: Marc Kupietz <kupietz@ids-mannheim.de>
diff --git a/pom.xml b/pom.xml
index 14f255e..7e5e108 100644
--- a/pom.xml
+++ b/pom.xml
@@ -207,7 +207,6 @@
 					<!-- <verbose>true</verbose>
 		          	<fork>true</fork> -->
 		         	<!-- <executable>${env.JAVA7_HOME}/bin/javac</executable> -->
-					<compilerVersion>2.0</compilerVersion>
 					<source>${java.version}</source>
 					<target>${java.version}</target>
 				</configuration>