Fix migration 0096 downgrade failing when team table has rows

[vatsrahul1001]

The downgrade() in 0096_3_2_0_remove_team_id.py tries to ADD COLUMN id VARCHAR(36) NOT NULL on the team table without providing a default or populating existing rows first.

• closes: airflow db downgrade fails on migration 0096 when team table has data #63444

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[vincbeck]

My bad! Thanks for the fix