fix typo

Author: reint-fischer

docs/user_guide/index.md

@@ -44,7 +44,7 @@ examples/tutorial_delaystart.ipynb
 :caption: Write Kernels
 :titlesonly:
 
-examples/kernelloop_explanation.md
+examples/explanation_kernelloop.md
 examples/tutorial_sampling.ipynb
 examples/tutorial_gsw_density.ipynb
 examples/tutorial_Argofloats.ipynb