chore: fix typos

Author: sinedied

sessions/01-llms.md

@@ -40,4 +40,4 @@ Another limit that you have to keep in mind is while these AI models are powerfu
 
 It's also why at Microsoft, we've been deeply committed to responsible AI. Responsible AI is a framework for building AI systems according to six principles. Fairness, reliability and safety, privacy and security, inclusiveness, transparency, and accountability. For Microsoft, these principles are the cornerstone of a responsible and trustworthy approach to AI, especially as intelligent technology becomes more and more present in products and services that people use every day. And this is not only for us. It's something that you also have to keep in mind when using AI models to build your own applications.
 
-In the next session, we'll talk about essential product engineering techniques that will help you get the best out of AI models.
+In the next session, we'll talk about essential prompt engineering techniques that will help you get the best out of AI models.

sessions/03-rag.md

@@ -36,4 +36,4 @@ Now, if we try to ask something that's not in the provided documents, let's see
 
 If you're interested in this sample, you can have a look at the links in the video description or here, and be sure to take a look at the other videos in the series to learn how we made it.
 
-In the next session, we'll see how you can speed up your AI developments using the Longchain JS framework.
+In the next session, we'll see how you can speed up your AI developments using the Langchain JS framework.