md: fix anchor

imba-tjd · web-flow · commit c5b027df1c5a · 2021-09-30T15:27:57.000+08:00
diff --git a/doc/tutorials/dockerfile.md b/doc/tutorials/dockerfile.md
@@ -48,7 +48,7 @@ Dockerfile. For example, this code sources the Jupyter-Scipy notebook:
 FROM jupyter/scipy-notebook:cf6258237ff9
 ```
 
-See [Preparing your Dockerfile](preparing your dockerfile) for instructions on how to
+See [Preparing your Dockerfile](#preparing-your-dockerfile) for instructions on how to
 do this properly.
 
 ### When you are building complex software
