Fix SQL syntax that could cause deadlocks

[harels]

/* SourceDao.upsert */ INSERT INTO sources (uuid, type, created_at, updated_at, name, connection_url ) VALUES ($1, $2, $3, $4, $5, $6) ON CONFLICT(name) DO UPDATE SET type = EXCLUDED.type, updated_at = EXCLUDED.updated_at, name = EXCLUDED.name, connection_url = EXCLUDED.connection_url RETURNING *
we should remove name = EXCLUDED.name since we know that it's the same name (because of the conflict)

[boring-cyborg]

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