Fix build issue

Author: leslieyip02

.github/workflows/jekyll-gh-pages.yml

@@ -48,4 +48,4 @@ jobs:
     steps:
       - name: Deploy to GitHub Pages
         id: deployment
-        uses: actions/deploy-pages@v2
+        uses: actions/deploy-pages@v4

git/slides.md

@@ -30,7 +30,7 @@ style: |
 PRESENTS
 
 Introduction to Git (and GitHub)
-18 May 2024
+17 May 2025
 
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