Add support for QUALIFY clause

[slessard]

Is your feature request related to a problem? Please describe. There are several SQL dialects that support the QUALIFY clause. One of those dialects is Teradata, the dialect I happen to work with. I need to build a query that uses the QUALIFY clause and need goqu to support that clause

Describe the solution you'd like Add support for the QUALIFY clause

Describe alternatives you've considered None considered

Dialect

• [ ] postgres
• [ ] mysql
• [ ] sqlite3
• [ ] sqlserver

Additional context https://docs.teradata.com/r/2_MC9vCtAJRlKle2Rpb0mA/19NnI91neorAi7LX6SJXBw https://docs.snowflake.com/en/sql-reference/constructs/qualify.html https://docs.databricks.com/sql/language-manual/sql-ref-syntax-qry-select-qualify.html https://duckdb.org/docs/sql/query_syntax/qualify https://www.omnidex.com/docs/v4x/SQL%20Reference/Commands/QUALIFY.htm