Update links in index.md to remove file extensions for consistency

Author: grongierisc

docs/index.md

@@ -30,6 +30,6 @@ pip install iris-pex-embedded-python
 
 ## Getting Started
 
-If you're new to this proof of concept, begin by reading the [installation guide](getting-started/installation.md). Then, follow the [first steps](getting-started/first-steps.md) to create your first Business Operation.
+If you're new to this proof of concept, begin by reading the [installation guide](getting-started/installation). Then, follow the [first steps](getting-started/first-steps) to create your first Business Operation.
 
 Happy coding!