Add guideline to avoid reflection in code and tests (#5784)

* Add guideline to avoid reflection in code and tests

Ensuring agents do not use reflection when coding

* Update .clinerules/msal-guidelines.md

Co-authored-by: Gladwin Johnson <90415114+gladjohn@users.noreply.github.com>

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Co-authored-by: Gladwin Johnson <90415114+gladjohn@users.noreply.github.com>

Author: trwalke

.clinerules/msal-guidelines.md

@@ -46,6 +46,7 @@ Through its comprehensive feature set and proven reliability, MSAL.NET simplifie
 - Implement proper error handling and retry logic
 - Keep dependencies minimal and well-justified
 - Document security considerations thoroughly
+- Do not use reflection in source code and tests.
 
 ### Authentication Best Practices
 - Use certificate-based authentication over client secrets when possible