chore: rename magazine (#44212)

* chore: rename files

* chore: update codebase

* chore: proper title case

curriculum/challenges/_meta/learn-css-grid-by-building-a-magazine/meta.json

@@ -1,7 +1,7 @@
 {
-  "name": "CSS Grid Magazine",
+  "name": "Learn CSS Grid by Building a Magazine",
   "isUpcomingChange": true,
-  "dashedName": "css-grid-magazine",
+  "dashedName": "learn-css-grid-by-building-a-magazine",
   "order": 16,
   "time": "5 hours",
   "template": "",