Update materials.yaml

Author: erdaifuu

_data/materials.yaml

@@ -13,7 +13,7 @@
   date: 2/11/2025
   name: Core Shell & Shell Scripting
   labdue: Sat. 2/15
-  hidelink: true
+  hidelink: false
   slides: https://docs.google.com/presentation/d/1Ia5c1xIXsUP-d3BNq8uE6OjgNRjXixsnaZtXbYHkSUs/edit?usp=sharing
   video: https://drive.google.com/file/d/1MLXH352y_9axpAuGpJbnE373dL4GL6CP/view?usp=sharing