Adjust versions

Author: wieck

Dockerfile

@@ -1,6 +1,6 @@
 # Note: This should be run, once Maven has build correctly the target directory.
 
-FROM rockylinux:8
+FROM rockylinux:8.6
 
 RUN dnf -y update
 

pom.xml

@@ -13,8 +13,8 @@
 
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<maven.compiler.source>11</maven.compiler.source>
-		<maven.compiler.target>11</maven.compiler.target>
+		<maven.compiler.source>1.8</maven.compiler.source>
+		<maven.compiler.target>1.8</maven.compiler.target>
 	</properties>
 
 	<!-- To check newer version of the dependencies, run the following: -->