fix: init file is needed for makemigrations

also make sure all migration files are formatted

Author: angela-tran

bin/makemigrations.sh

@@ -1,9 +1,14 @@
 #!/usr/bin/env bash
 set -eux
 
-# copy old migrations to temporary directory
+# create temporary directory (if it doesn't already exist)
 
-cp -r benefits/core/migrations benefits/core/old_migrations
+mkdir -p benefits/core/old_migrations
+
+# move old migrations to temporary directory, but keep init file
+
+mv benefits/core/migrations/* benefits/core/old_migrations
+cp benefits/core/old_migrations/__init__.py benefits/core/migrations
 
 # regenerate
 
@@ -14,8 +19,9 @@ python manage.py makemigrations
 cp benefits/core/old_migrations/* benefits/core/migrations --no-clobber --recursive
 
 # clean up temporary directory
+
 rm -rf benefits/core/old_migrations
 
 # reformat with black
 
-python -m black benefits/core/migrations/0001_initial.py
+python -m black benefits/core/migrations/*