chore: update plugin description

Author: rsbowers

src/app/code/community/Zendesk/Zendesk/etc/system.xml

@@ -92,14 +92,14 @@
                             <comment><![CDATA[Depending on your Zendesk configuration under "Settings / Security / JSON Web Token / Update of external IDs?" ]]></comment>
                         </use_external_id>
                         <customer_sync translate="label comment">
-                            <label>Synchronize Customers</label>
+                            <label>Synchronize Customers (*Experimental)</label>
                             <frontend_type>select</frontend_type>
                             <source_model>adminhtml/system_config_source_yesno</source_model>
                             <sort_order>6</sort_order>
                             <show_in_default>1</show_in_default>
                             <show_in_website>1</show_in_website>
                             <show_in_store>1</show_in_store>
-                            <comment><![CDATA[Synchronize magento customer accounts with zendesk end-users? ]]></comment>
+                            <comment><![CDATA[Synchronize magento customer accounts with zendesk end-users? NOTE: Experimental, use at your own risk.]]></comment>
                         </customer_sync>
                         <sync_now translate="button_label comment">
                             <label></label>