Merge "Fix url in alembic_migrations.rst"

doc/source/contributor/alembic_migrations.rst

@@ -113,7 +113,7 @@ Neutron makes use of alembic branches for two purposes.
 1. Independent Sub-Project Tables
 ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 
-Various `sub-projects <../stadium/sub_projects.html>`_ can be installed with Neutron. Each
+Various `Sub-Projects <../contributor/stadium/guidelines.html>`_ can be installed with Neutron. Each
 sub-project registers its own alembic branch which is responsible for migrating
 the schemas of the tables owned by the sub-project.