chore: add remark and plugin keywords in _tools/remark/plugins/remark-run-javascript-examples

The package is a remark plugin yet lacked the `remark` and `plugin`
keywords carried by 11 of 14 sibling packages in
`@stdlib/_tools/remark/plugins`. Adding both restores the namespace
keyword convention.

Author: claude

lib/node_modules/@stdlib/_tools/remark/plugins/remark-run-javascript-examples/package.json

@@ -45,6 +45,8 @@
     "examples",
     "demo",
     "javascript",
-    "js"
+    "js",
+    "remark",
+    "plugin"
   ]
 }