Update manifest.json

Change name from "Documentation AI butler" to "DocsGPT - Documentation AI butler"; Fixed spelling

extensions/chrome/manifest.json

@@ -1,5 +1,5 @@
 {
-  "name": "Documenation AI butler",
+  "name": "DocsGPT - Documentation AI butler",
   "version": "0.0.1",
   "manifest_version": 2,
   "description": "AI assistant for developers, that helps you answer your questions about the documentation you are reading.",
@@ -18,4 +18,4 @@
     "default_popup": "popup.html"
 }
 
-}
+}