Replace hyperlink for using a SQL expression in a data test

README.md

@@ -536,7 +536,7 @@ We generally recommend testing this uniqueness condition by either:
 
 - generating a [surrogate_key](#generate_surrogate_key-source) for your model and testing
 the uniqueness of said key, OR
-- passing the `unique` test a concatenation of the columns (as discussed [here](https://docs.getdbt.com/docs/building-a-dbt-project/testing-and-documentation/testing/#testing-expressions)).
+- passing the `unique` test a concatenation of the columns (as discussed [here](https://docs.getdbt.com/reference/resource-properties/data-tests#test-an-expression)).
 
 However, these approaches can become non-perfomant on large data sets, in which
 case we recommend using this test instead.