ruff

835e31b3 - Fix syntax error false positive on alternative `match` patterns (#21362)

Fix syntax error false positive on alternative `match` patterns (#21362) Summary -- Fixes #21360 by using the union of names instead of overwriting them, as Micha suggested originally on #21104. This avoids overwriting the `n` name in the `Subscript` by the empty set of names visited in the nested OR pattern before visiting the other arm of the outer OR pattern. Test Plan -- A new inline test case taken from the issue