fix #10287 (#10448)

The only thing separating these two files
(which wrongly appear on index.html as modules)
and the rest of the (correctly placed)
documents was the style of the title :D

doc/contributing.rst

@@ -1,6 +1,10 @@
+============
 Contributing
 ============
 
+.. contents::
+
+
 Contributing happens via "Pull requests" (PR) on github. Every PR needs to be
 reviewed before it can be merged and the Continuous Integration should be green.
 
@@ -120,7 +124,7 @@ To run a single test:
 ::
 
   ./koch tests c <category>/<name>
-  
+
 E.g. ``./koch test run stdlib/thttpclient_ssl``
 
 For reproducible tests (to reproduce an environment more similar to the one

doc/packaging.rst

@@ -1,3 +1,4 @@
+=============
 Packaging Nim
 =============