Add DAG to dbt modeling PR template.

Author: jaypeedevlin

pr_templates/dbt_modeling_pr.md

@@ -3,6 +3,7 @@ _Summarize the goal of your work and what motivated it._
 
 ## Key changes
 - _Describe major updates._
+- _If the PR creates or renames models or adds references between models, paste a screenshot of the relevant parts of the lineage graph._
 
 ## Other notes
 - _List open questions and other things your reviewer should know._
@@ -16,7 +17,7 @@ _Summarize the goal of your work and what motivated it._
 - [ ] New code follows [dbt coding conventions](https://github.com/brooklyn-data/co/blob/master/dbt_coding_conventions.md) and [SQL style guide](https://github.com/brooklyn-data/co/blob/master/sql_style_guide.md).
 - [ ] Testing:
     - [ ] All added/modified models and columns are documented and tested in `schema.yml` files.
-    - [ ] All tests pass. **OR**    
+    - [ ] All tests pass. **OR**
     _Check one:_
     - [ ] There are no new test failures, whether or not the existing model was intentionally changed for this PR.
     - [ ] This PR causes new test failures and there is a plan in place for addressing them.