Add external package for doc search

Author: yashovardhan

package.json

@@ -33,6 +33,7 @@
     "classnames": "^2.5.1",
     "clsx": "^1.2.1",
     "copy-to-clipboard": "^3.3.3",
+    "docusaurus-openai-search": "^1.0.0",
     "gray-matter": "^4.0.3",
     "hast-util-is-element": "^1.1.0",
     "joi": "^17.13.3",