fix: broken quickstart sample flow and empty events in toc (#227)

What was Added?

- Added a fix for only adding the events section in TOC when an API spec containing Webhooks/Callbacks was provided.
- Added a missing check for verifying validation was successful when checking unallowed features.

---------

Co-authored-by: Ayesha <88117894+Ayeshas09@users.noreply.github.com>

Author: aliasghar98

README.md

@@ -24,7 +24,7 @@ $ npm install -g @apimatic/cli
 $ apimatic COMMAND
 running command...
 $ apimatic (--version)
-@apimatic/cli/1.1.0-beta.3 win32-x64 node-v23.4.0
+@apimatic/cli/1.1.0-beta.5 win32-x64 node-v23.4.0
 $ apimatic --help [COMMAND]
 USAGE
   $ apimatic COMMAND