E2: Make rule smarter when applied to UNNEST joins

[fabio-looker]

For example:

join: nested {
  sql: LEFT JOIN UNNEST(nested) ;;
  relationship: many_to_one
}

(Potentially also if using sql_table_name, though this would be less common since an ON clause is normally removed with UNNEST)

[Rkohn123]

Hello, I totally agree with this feature I have exactly this error like right now :)