Remove client option for JVM for plugins script

Today we specify the client option for the JVM when executing plugin
commands. Yet, this option does nothing on a 64-bit capable JDK as such
JDKs always select the Hotspot server VM. And for 32-bit JDKs, running
plugin commands with the server VM is okay. Thus, we should just remove
this unnecessary flag and just let the default VM be selected.

Relates #18142

distribution/src/main/resources/bin/elasticsearch-plugin

@@ -110,4 +110,4 @@ fi
 HOSTNAME=`hostname | cut -d. -f1`
 export HOSTNAME
 
-eval "\"$JAVA\"" "$ES_JAVA_OPTS" -client -Delasticsearch -Des.path.home="\"$ES_HOME\"" $properties -cp "\"$ES_HOME/lib/*\"" org.elasticsearch.plugins.PluginCli $args
+eval "\"$JAVA\"" "$ES_JAVA_OPTS" -Delasticsearch -Des.path.home="\"$ES_HOME\"" $properties -cp "\"$ES_HOME/lib/*\"" org.elasticsearch.plugins.PluginCli $args