Revert "add search"

[nellshamrell]

Reverts #3942

Unfortunately, this change seems to have broken our workflow for creating the html for the This Week in Rust emails (which is different from what appears on the site).

When I run our email generation flow:

(from the publishing directory):

 make build && make generate-email && make host-content

I get these errors:

Use 'docker scan' to run Snyk tests against images to find vulnerabilities and learn how to fix them
/home/nell/rust/this-week-in-rust/publishing
rm -rf output/
docker run -it \
        -e TWIR_NEWSLETTER_THEME=1 \
        -v /home/nell/rust/this-week-in-rust/publishing/output:/usr/twir/output \
        twir:latest
[20:04:22] CRITICAL Exception: Search plugin reported Error: All files failed to be indexed.                                                        __init__.py:550
                    Warning: Stork couldn't include 486 files in the index because of the following errors:
                    In file `pages/privacy-policy.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/02/15/this-week-in-rust-482/index.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/02/08/this-week-in-rust-481/index.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/02/01/this-week-in-rust-480/index.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/01/25/this-week-in-rust-479/index.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/01/18/this-week-in-rust-478/index.html`: The selector `article` is not present in the HTML document.
                    In file `blog/2023/01/11/this-week-in-rust-477/index.html`: The selector `article` is not present in the HTML document.

Rolling back for the time being until we can address this.