fix: multiple plugin install

Author: miyataka

entrypoint.sh

@@ -15,11 +15,11 @@ MAJOR_VERSION=`echo ${STACK_VERSION} | cut -c 1`
 PLUGIN_INSTALL_CMD=""
 
 if [ "x${PLUGINS_STR}" != "x" ]; then
-    ARRAY=(${PLUGINS_STR})
-    for i in ${ARRAY}
+    for i in "${PLUGINS_STR}"
     do
         PLUGIN_INSTALL_CMD+="elasticsearch-plugin install --batch ${i} &&"
     done
+    echo ${PLUGIN_INSTALL_CMD}
 fi
 
 # single node only