text: Title: Ability to poll db to pull current alembic version
  Body: ### **Desired Behavior**
  
  When running a new build from Jenkins it creates a new build environment 'flask db init' migration folder and has the ability to poll the database to pull the current alembic version and then perform migration, upgrade, downgrade as needed as the migrations folder is not saved between build environments or between builds.
  
  ### **Current Behavior**
  I need to remove the current alembic table from the database OR save the migrations folder and move it between builds and build environments to then perform an upgrade otherwise I receive the following complaint.
  
  (venv) root@build1:~/manual_build_dirs/balance_service# flask db migrate
  INFO  [alembic.runtime.migration] Context impl PostgresqlImpl.
  INFO  [alembic.runtime.migration] Will assume transactional DDL.
  ERROR [root] Error: Can't locate revision identified by '42f262e6ba92'
  
  
  **### Environment**
  * Python version: 3.6.9
  * Flask-SQLAlchemy version: 2.4.4
  * Flask-Migrate version: 2.5.3
  * SQLAlchemy version: 1.3.19
  