Remove compiling with -Werror to support Java 19 (apache#3820)

Author: merlimat

pom.xml

@@ -930,7 +930,6 @@
           <source>${javac.target}</source>
           <target>${javac.target}</target>
           <compilerArgs>
-            <compilerArg>-Werror</compilerArg>
             <compilerArg>-Xlint:deprecation</compilerArg>
             <compilerArg>-Xlint:unchecked</compilerArg>
             <!-- https://issues.apache.org/jira/browse/MCOMPILER-205 -->