Adding 🎓 to v3 to v4 migration guide titles

For consistency with rest of docs

Author: erikvansebille

docs/user_guide/index.md

@@ -16,7 +16,7 @@ getting_started/installation.md
 ```
 
 ```{note}
-If you have code that uses Parcels v3, you can migrate to Parcels v4 using [this migration guide](v4-migration.md)
+If you have code that uses Parcels v3, you can migrate to Parcels v4 using [🎓 the v3 to v4 migration guide](v4-migration.md)
 ```
 
 ## Getting started
@@ -125,9 +125,12 @@ examples/tutorial_interaction.ipynb
 
 <!-- examples/documentation_homepage_animation.ipynb -->
 
+## Other
+
 ```{toctree}
-:hidden:
 :caption: Other
-v3 to v4 migration guide <v4-migration>
+:name: other
+:titlesonly:
+🎓 v3 to v4 migration guide <v4-migration>
 Example scripts <additional_examples>
 ```

docs/user_guide/v4-migration.md

@@ -2,7 +2,7 @@
 html_theme.sidebar_secondary.remove: true
 ---
 
-# Parcels v4 migration guide
+# 🎓 Parcels v4 migration guide
 
 This migration guide gives some tips if you want to migrate your Parcels v3 code to Parcels v4. The biggest changes are in the [Kernel API](#kernels) and the way that [FieldSets are created](#fieldset). The other changes are mostly small and should be easy to fix.