🗑️ Clean up codesee GA workflow (#254)

The CodeSee platform will be shutting down on Thursday, Feb 22nd.

Copy of
[instructions](https://docs.codesee.io/docs/uninstall-codesee-from-github-repos?utm_campaign=Shut+down&utm_content=Shut+down&utm_medium=email_action&utm_source=customer.io):

> Uninstall CodeSee from GitHub repos

> On Feb 22nd we'll be removing the CodeSee app from the GitHub app
store. The CodeSee application will automatically be removed from your
installed apps list, but you will need to take additional steps to
remove the CodeSee action and secrets.
> 
> 1. Remove the CodeSee GitHub action from each repo
> Delete .github/workflows/codesee-arch-diagram.yml from each repo to
remove the CodeSee GitHub action.
> 
> 2. Remove the CodeSee secret
> Navigate to the main page for your repo
(github.com/orginization/repo-name) and click on settings --> secrets
and variables --> actions.
> 
> Click the trash can icon next to CODESEE_ARCH_DIAG_API_TOKEN to delete
the CodeSee application secret.
> 
> Note: CODESEE_ARCH_DIAG_API_TOKEN may exist in either/both of the
Repository secrets and Organization secrets sections.
> 
> 3. You're all set!
> CodeSee has been successfully uninstalled!