`DropIndexOp` does not render keyword arguments such as `postgresql_concurrently`

[jetzhou]

Describe the bug
1011366 added kwargs support to drop index operation in SQL generation. However, in autogenerate render step, an operation such as this one:

alembic.operations.ops.DropIndexOp(
    'example_index',
    postgresql_concurrently=True,
)

will be rendered to

op.drop_index(op.f('example_index'))

which ignores the postgresql_concurrently kwarg.

Expected behavior

alembic.operations.ops.DropIndexOp(
    'example_index',
    postgresql_concurrently=True,
)

should render in autogenerate to

op.drop_index(op.f('example_index'), postgresql_concurrently=True)

To Reproduce
Test code that does not pass

    def test_render_drop_index_custom_kwarg(self):
        t = Table(
            "test",
            MetaData(),
            Column("id", Integer, primary_key=True),
            Column("active", Boolean()),
            Column("code", String(255)),
        )
        idx = Index(None, t.c.active, t.c.code, somedialect_foobar="option")
        op_obj = ops.DropIndexOp.from_index(idx)
        eq_ignore_whitespace(
            autogenerate.render_op_text(self.autogen_context, op_obj),
            "op.drop_index(op.f('ix_test_active'), table_name='test', "
            "somedialect_foobar='option')",
        )

Versions.

• OS: Ubuntu 21.04
• Python: 3.9.5
• Alembic: 1.6.4
• SQLAlchemy: 1.3.19
• Database: PostgreSQL
• DBAPI: psycopg

Additional context
Proposed fix: jetzhou@6392a28

Have a nice day!

[zzzeek]

will have to look and see if we have existing precedent for this, which I think we should, like for indexes etc.

[zzzeek]

looks like you have a fix ready! that's a PR, please send. I assume most of the other constructs are OK in this regard

[jetzhou]

Thanks @zzzeek for the triage! Created PR for this.

[zzzeek]

thanks for following all the guidelines on this! most people dont :) but it makes it easy

[sqla-tester]

Jet Zhou has proposed a fix for this issue in the master branch:

Add kwargs support to DropIndexOp autogenerate render https://gerrit.sqlalchemy.org/c/sqlalchemy/alembic/+/2844

[zzzeek]

thanks! 1.6.5 is released.

[jetzhou]

Woohoo! Thanks for taking a look and the quick + efficient PR prorcess!