Update sources.md

add link to source directly. committing to current since it's a small link addition

website/docs/docs/build/sources.md

@@ -14,7 +14,7 @@ search_weight: "heavy"
 
 ## Using sources
 Sources make it possible to name and describe the data loaded into your warehouse by your Extract and Load tools. By declaring these tables as sources in dbt, you can then
-- select from source tables in your models using the `{{ source() }}` function, helping define the lineage of your data
+- select from source tables in your models using the [`{{ source() }}` function,](/reference/dbt-jinja-functions/source) helping define the lineage of your data
 - test your assumptions about your source data
 - calculate the freshness of your source data