Include non-transaction pages in start-button-links table

[nacnudus]

Start buttons can be created in GovSpeak, and in fact any button can be created there. For example:

SELECT
  content.base_path
FROM
  public.content
INNER JOIN
  public.publishing_api_editions_current AS editions
ON
  editions.id = content.edition_id
WHERE
  CONTAINS_SUBSTR(html, "govuk-button")
  AND editions.document_type <> 'transaction'

These should be included in the start-button-links table.

govuk-knowledge-graph-gcp/terraform/bigquery/start-button-links.sql

Line 17 in ea8ea2c

INSERT INTO public.start_button_links