It seems that the reason why the `test_select_with_subquery_in_from_uses_original_table_name`
does not pass is that the return value of `sqlite3_column_name()` is
wrong due to subquery flattening.

This seems to have been fixed with SQLite 3.20.0(https://sqlite.org/changes.html#version_3_20_0).
But CI uses the old version(maybe 3.11.0), I added `DISTINCT` to avoid
optimization by subquery flattening.

Ref: https://sqlite.org/optoverview.html#flattening