.Net: Added a notebook for vector stores (#9390)

### Motivation and Context

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Resolves: #7607

This PR contains a .NET notebook for vector stores demonstrating main
functionality and components. It also contains several links with more
information about vector stores on Microsoft Learn portal.

### Contribution Checklist

<!-- Before submitting this PR, please make sure: -->

- [x] The code builds clean without any errors or warnings
- [x] The PR follows the [SK Contribution
Guidelines](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md)
and the [pre-submission formatting
script](https://github.com/microsoft/semantic-kernel/blob/main/CONTRIBUTING.md#development-scripts)
raises no violations
- [x] All unit tests pass, and I have added new tests where possible
- [x] I didn't break anyone 😄

---------

Co-authored-by: westey <[email protected]>

dotnet/README.md

@@ -77,11 +77,11 @@ requirements and setup instructions.
 3. [Running AI prompts from file](./notebooks/02-running-prompts-from-file.ipynb)
 4. [Creating Semantic Functions at runtime (i.e. inline functions)](./notebooks/03-semantic-function-inline.ipynb)
 5. [Using Kernel Arguments to Build a Chat Experience](./notebooks/04-kernel-arguments-chat.ipynb)
-6. [Introduction to the Planning/Function Calling](./notebooks/05-using-function-calling.ipynb)
-7. [Building Memory with Embeddings](./notebooks/06-memory-and-embeddings.ipynb)
+6. [Introduction to the Function Calling](./notebooks/05-using-function-calling.ipynb)
+7. [Vector Stores and Embeddings](./notebooks/06-vector-stores-and-embeddings.ipynb)
 8. [Creating images with DALL-E 3](./notebooks/07-DALL-E-3.ipynb)
 9. [Chatting with ChatGPT and Images](./notebooks/08-chatGPT-with-DALL-E-3.ipynb)
-10. [BingSearch using Kernel](./notebooks/10-RAG-with-BingSearch.ipynb)
+10. [BingSearch using Kernel](./notebooks/09-RAG-with-BingSearch.ipynb)
 
 # Semantic Kernel Samples