Move netty numDirectArenas to jvm.options (#46104)

We currently configure io.netty.allocator.numDirectArenas to be 0 in the
jvm erconomics class. This is a config that we always want to set, so it
makes sense to move it to jvm.options.

distribution/src/config/jvm.options

@@ -81,6 +81,7 @@
 -Dio.netty.noUnsafe=true
 -Dio.netty.noKeySetOptimization=true
 -Dio.netty.recycler.maxCapacityPerThread=0
+-Dio.netty.allocator.numDirectArenas=0
 
 # log4j 2
 -Dlog4j.shutdownHookEnabled=false

distribution/tools/launchers/src/main/java/org/elasticsearch/tools/launchers/JvmErgonomics.java

@@ -64,9 +64,6 @@ final class JvmErgonomics {
                 ergonomicChoices.add("-Dio.netty.allocator.type=pooled");
             }
         }
-        if (systemProperties.containsKey("io.netty.allocator.numDirectArenas") == false) {
-            ergonomicChoices.add("-Dio.netty.allocator.numDirectArenas=0");
-        }
         final long maxDirectMemorySize = extractMaxDirectMemorySize(finalJvmOptions);
         if (maxDirectMemorySize == 0) {
             ergonomicChoices.add("-XX:MaxDirectMemorySize=" + heapSize / 2);