_content/doc: fix a broken link to Querying topic

This change fixes a link from /doc/database/change-data
to /doc/database/querying.

Change-Id: I76b57d0df17b4ef65dc02afd0a1f33aeef262243
Reviewed-on: https://go-review.googlesource.com/c/website/+/332251
Reviewed-by: Russ Cox <rsc@golang.org>
Trust: Steve Traut <straut@google.com>

_content/doc/database/change-data.md

@@ -7,7 +7,7 @@ When you perform database actions that don't return data, use an `Exec` or
 execute this way include `INSERT`, `DELETE`, and `UPDATE`.
 
 When your query might return rows, use a `Query` or `QueryContext` method
-instead. For more, see [Querying a database](/doc/database/query).
+instead. For more, see [Querying a database](/doc/database/querying).
 
 An `ExecContext` method works as an `Exec` method does, but with an additional
 `context.Context` argument, as described in