Rename past-bugs-by-function task to past-bugs-by-unit

Follow-up to 2f78dc1643

infra/data-pipeline.yml

@@ -744,7 +744,7 @@ tasks:
         owner: release-mgmt-analysis@mozilla.com
         source: ${repository}/raw/master/data-pipeline.yml
 
-    - ID: past-bugs-by-function
+    - ID: past-bugs-by-unit
       created: {$fromNow: ''}
       deadline: {$fromNow: '1 day'}
       expires: {$fromNow: '1 month'}
@@ -1283,7 +1283,7 @@ tasks:
       deadline: {$fromNow: '2 days'}
       expires: {$fromNow: '1 month'}
       dependencies:
-        - past-bugs-by-function
+        - past-bugs-by-unit
         - train-regressor
       scopes:
         - hooks:modify-hook:project-bugbug/bugbug-classify-patch