Upgrade procedure for this change:
1. Stop the myems-normalization service or container.
2. Backup your database.
3. Upgrade myems/admin, myems/myems-api, and myems/myems-normalization source code,
and keep previous .env files unchanged.
4. Run database/upgrade/upgrade1.4.0.sql to merge expression into virtual meter
5. Check the virtual meters in Admin UI.
6. Start the myems-normalization service or container.