docs: move on_fit_end hook to teardown stage. (#21143)

* docs: move `on_fit_end` hook to `teardown` stage.
* Apply suggestion from @bhimrazy

---------

Co-authored-by: Bhimraj Yadav <[email protected]>

Author: GdoongMathew

docs/source-pytorch/common/hooks.rst

@@ -213,13 +213,14 @@ with the source of each hook indicated:
     │   ├── [LightningModule]
     │   └── [Strategy]
     │
-    ├── on_fit_end()
-    │   ├── [Callbacks]
-    │   ├── [LightningModule]
-    │   └── [Strategy]
-    │
     └── teardown(stage="fit")
-        └── [Callbacks only]
+        ├── [Strategy]
+        ├── on_fit_end()
+        │   ├── [Callbacks]
+        │   └── [LightningModule]
+        ├── [LightningDataModule]
+        ├── [Callbacks]
+        └── [LightningModule]
 
 ***********************
 Testing Loop Hook Order