Fix migration init from scratch

[raphaelrpl]

I've been facing issues while generating migrations from scratch database. It seems like the alembic is executing wrong order.

INFO [alembic.runtime.migration] Context impl PostgresqlImpl.
INFO [alembic.runtime.migration] Will assume transactional DDL.
INFO [alembic.runtime.migration] Running upgrade -> 03d259000eac, create-initial-tables
INFO [alembic.runtime.migration] Running upgrade 03d259000eac -> e8b12ba52665, create classes view.
INFO [alembic.runtime.migration] Running upgrade e8b12ba52665 -> d3db4a1a7f75, add_index
INFO [alembic.runtime.migration] Running upgrade d3db4a1a7f75 -> 237031a776fb, revision-0_6
INFO [alembic.runtime.migration] Running upgrade 237031a776fb -> 91c0103d0284, add_unique_in_class
INFO [alembic.runtime.migration] Running upgrade 03d259000eac -> 432e3447c36b, v0.4.0
INFO [alembic.runtime.migration] Running upgrade 432e3447c36b -> 02d16d3da520, 0.4.1
INFO [alembic.runtime.migration] Running upgrade 02d16d3da520 -> f3f27ad116d2, timeline
INFO [alembic.runtime.migration] Running upgrade f3f27ad116d2 -> be5ae740887a, v0.6.0
INFO [alembic.runtime.migration] Running upgrade be5ae740887a -> 566a05da999d, edit enums
INFO [alembic.runtime.migration] Running upgrade 91c0103d0284 -> 803fd73df983, rename_system_table.
INFO [alembic.runtime.migration] Running upgrade 803fd73df983 -> 83db828c55ad, system_lineage.
INFO [alembic.runtime.migration] Running upgrade 83db828c55ad -> 561ebe6266ad, internationalization
INFO [alembic.runtime.migration] Running upgrade 566a05da999d -> c68b17b1860b, v0.8.0.
File "/home/user/bdc-catalog/venv/lib/python3.9/site-packages/sqlalchemy/engine/default.py", line 732, in do_execute
cursor.execute(statement, parameters)
sqlalchemy.exc.ProgrammingError: (psycopg2.errors.UndefinedTable) relation "lccs.class_systems" does not exist

We should review c68b17b1860b_v0_8_0.py and add way to walkthrough.