change rules for SQLIte batch alter_column for special cases

[zzzeek]

Discussed in #882

According to this SQLite's official document, "add column" with a primary key or unique key constraint, or having some kinds of server default needs the recreate style:

https://www.sqlite.org/lang_altertable.html#alter_table_add_column

code here we are changing is in sqlite.py

[sqla-tester]

Mike Bayer has proposed a fix for this issue in the master branch:

qualify sqlite batch add column for dynamic defaults https://gerrit.sqlalchemy.org/c/sqlalchemy/alembic/+/2995