Update capitalisation

index.qmd

@@ -6,7 +6,7 @@ This is a series of short lessons in various technologies useful to our work.
 
 The first step is to read over the lesson Github Collaboration.
 
-### summary
+### Summary
 
 1. Make a branch for your lesson.
 2. Create a Quarto markdown document with `## Objectives` and `## Key points` and add it to that branch.