Brief summary of the change made

• Add zip and zip_strict dbt built-in jinja2 functions. (from the official doc: https://docs.getdbt.com/reference/dbt-jinja-functions/zip)

Why

• These missing functions will break the linting even even when we configure apply_dbt_builtins=true

How to reproduce

sqlfluff lint --templater=jinja --dialect bigquery --ignore="templating, parsing" -<<EOF
{% set cols = ['c1', 'c2', 'c3'] %}
{% set tables = ['alice', 'bob', 'tim'] %}

{% for (c, t) in zip(cols, tables) %}
select
  {{ c }} as col
from
  {{ t }}
{% if not loop.last %}
  union all
{% endif %}
{% endfor %}
EOF

This will throw a ValueError because zip is not a built-in jinja2 function.

Are there any other side effects of this change that we should be aware of?

Pull Request checklist

• Please confirm you have completed any of the necessary steps below.

• Included test cases to demonstrate any code changes, which may be one or more of the following:

  • .yml rule test cases in test/fixtures/rules/std_rule_cases.
  • .sql/.yml parser test cases in test/fixtures/dialects (note YML files can be auto generated with tox -e generate-fixture-yml).
  • Full autofix test cases in test/fixtures/linter/autofix.
  • Other.

• Added appropriate documentation for the change.

• Created GitHub issues for any relevant followup/future enhancements if appropriate.