Fix javadoc version

Author: tastybento

pom.xml

@@ -351,7 +351,7 @@
                     <doclint>none</doclint>  <!-- Turnoff all checks -->
                     <failOnError>false</failOnError>
                     <javadocExecutable>${java.home}/bin/javadoc</javadocExecutable>
-                    <source>17</source>
+                    <source>21</source>
                 </configuration>
                 <executions>
                     <execution>