Update README.md

Author: andreibondarev

README.md

@@ -6,4 +6,4 @@ This tiny script utilizes the Langchain.rb Assistant and Tools to classify a blo
 1. `git clone https://github.com/patterns-ai-core/blog-post-classifier-demo.git`
 2. `bundle install`
 3. `cp .env.example .env` and fill it out with your `OPENAI_API_KEY`.
-4. `ruby classifier.rb --path=blog_post.txt`
+4. `ruby classifier.rb --file=blog_post.txt`