insert+overwrite incremental strategy for iceberg tables incorrectly uses a partition clause

[amaralvieira]

From the docs:

Since Iceberg uses hidden partitioning it means you don't need a partition clause in your INSERT statements.

The current get_insert_overwrite_sql macro throws an error whenever the iceberg table uses partition transforms. This can be avoided altogether by omitting the partition clause. For example:

    {% if table_type == 'iceberg' -%}
        {%- if raw_strategy == 'insert_overwrite' %}
            insert overwrite {{ target }} ({{ dest_cols_csv }})
            select {{ dest_cols_csv }} from {{ source }}
        {%- elif raw_strategy == 'append' %}
            insert into {{ target }} ({{ dest_cols_csv }})
            select {{ dest_cols_csv }} from {{ source }}
        {%- endif %}
    {% else %}

It would probably be a good idea to add a check somewhere for the case someone tries to set a INSERT OVERWRITE incremental strategy for tables that use the BUCKET transform (as it is not allowed).