DEV: Break up PG query in MakePasswordColumnsFromUsersReadOnly (#29167)

We are getting a lock timeout but I can't tell which statement so break
it up.

db/post_migrate/20240910090759_make_password_columns_from_users_read_only.rb

@@ -2,10 +2,19 @@
 class MakePasswordColumnsFromUsersReadOnly < ActiveRecord::Migration[7.1]
   def up
     # remove invalid triggers/functions dependent on the columns to be dropped
-    execute <<~SQL.squish
+    execute <<~SQL
       DROP TRIGGER IF EXISTS users_password_sync_on_delete_password ON users;
+    SQL
+
+    execute <<~SQL
       DROP FUNCTION IF EXISTS delete_user_password;
+    SQL
+
+    execute <<~SQL
       DROP TRIGGER IF EXISTS users_password_sync ON users;
+    SQL
+
+    execute <<~SQL
       DROP FUNCTION IF EXISTS mirror_user_password_data;
     SQL