Fix link to change_4639in `doc/build/changelog/migration_20.rst` (#10585)

diff --git a/doc/build/changelog/migration_20.rst b/doc/build/changelog/migration_20.rst
index 8df134721e72ca8d0410b073f72f374b15311153..fe86338ee21295446c67dbbce19b524dfbc68018 100644 (file)
--- a/doc/build/changelog/migration_20.rst
+++ b/doc/build/changelog/migration_20.rst
@@ -1687,7 +1687,7 @@ ORM-specific compiler plugins receive the
 :class:`_sql.Select` construct and interpret its contents in terms of an
 ORM-style query, before passing off to the core-level compiler in order to
 create a SQL string.  With the advent of the new
-`SQL compilation caching system <change_4639>`,
+:ref:`SQL compilation caching system <change_4639>`,
 the majority of this ORM logic is also cached.