update mapping for coc explorer

coc-settings.json

@@ -64,7 +64,7 @@
   "explorer.previewAction.onHover": false,
   "explorer.icon.enableVimDevicons": false,
   "explorer.file.showHiddenFiles": false,
-  "explorer.keyMappings": {
+  "explorer.keyMappings.global": {
     "<cr>": ["expandable?", "expand", "open"],
     "v": "open:vsplit"
   },