Fix bug in pooch example

pooch needs URL pointing to raw data to work

docs/source/open_science/GIN-repositories.md

@@ -295,13 +295,14 @@ Here is a simple example of how to download a dataset from a GIN repository usin
 import pooch
 
 filepath = pooch.retrieve(
-    url="https://gin.g-node.org/<username>/<repository>/src/main/file",
+    url="https://gin.g-node.org/<username>/raw/<repository>/main/file",
     known_hash=None,
     path="/home/<user>/downloads", # this is where the file will be saved
     progressbar=True,
 )
 ```
 
+
 ## Some under-the-hood details
 
 GIN is a wrapper around [git-annex](https://git-annex.branchable.com/). The high-level idea behind git-annex is: