Deleting as_text page (#4726)

## What are you changing in this pull request and why?

The filter function referenced on this page hasn't done anything since
dbt Core v0.17.0.

As this version is wildly outdated, we are deleting the page

Nothing to delete from sidebar.js as this is autogenerated

## Checklist
<!--
Uncomment when publishing docs for a prerelease version of dbt:
- [ ] Add versioning components, as described in [Versioning
Docs](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#versioning-entire-pages)
- [ ] Add a note to the prerelease version [Migration
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- [x] Review the [Content style
guide](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/content-style-guide.md)
so my content adheres to these guidelines.
- [x] For [docs
versioning](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#about-versioning),
review how to [version a whole
page](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#adding-a-new-version)
and [version a block of
content](https://github.com/dbt-labs/docs.getdbt.com/blob/current/contributing/single-sourcing-content.md#versioning-blocks-of-content).
- [x] Add a checklist item for anything that needs to happen before this
PR is merged, such as "needs technical review" or "change base branch."

Adding or removing pages (delete if not applicable):
- [x] Add/remove page in `website/sidebars.js`
- [ ] Provide a unique filename for new pages
- [ ] Add an entry for deleted pages in `website/static/_redirects`
- [ ] Run link testing locally with `npm run build` to update the links
that point to deleted pages

website/docs/docs/dbt-versions/core-upgrade/11-Older versions/upgrading-to-0-17-0.md

@@ -248,8 +248,8 @@ BigQuery:
 
 **Core**
 - [`path:` selectors](/reference/node-selection/methods#the-path-method)
-- [`--fail-fast`](/reference/commands/run#failing-fast)
-- [as_text Jinja filter](/reference/dbt-jinja-functions/as_text)
+- [`--fail-fast` command](/reference/commands/run#failing-fast)
+- `as_text` Jinja filter: removed this defunct filter
 - [accessing nodes in the `graph` object](/reference/dbt-jinja-functions/graph)
 - [persist_docs](/reference/resource-configs/persist_docs)
 - [source properties](reference/source-properties)

website/vercel.json

@@ -3633,8 +3633,8 @@
       "permanent": true
     },
     {
-      "source": "/docs/writing-code-in-dbt/jinja-context/as_text",
-      "destination": "/reference/dbt-jinja-functions/as_text",
+      "source": "/reference/dbt-jinja-functions/as_text",
+      "destination": "/reference/dbt-jinja-functions",
       "permanent": true
     },
     {