VACMS-19516 Email signup form disable analytics

[randimays]

Are you removing, renaming or moving a folder in this PR?

• [x] No, I'm not changing any folders (skip to TeamSites and delete the rest of this section)
• [ ] Yes, I'm removing, renaming or moving a folder

:warning: TeamSites :warning:

Did you change site-wide styles, platform utilities or other infrastructure?

• [x] No
• [ ] Yes, and I used the proxy-rewrite steps to test the injected header scenario

Summary

Disable web component analytics for the va-button in the email signup form on the homepage.

Related issue(s)

https://github.com/department-of-veterans-affairs/va.gov-cms/issues/19516

Testing done

Checked analytics when clicking the Sign up button. Only this custom event should appear:

{
  event: 'homepage-email-sign-up'
  button-click-label: 'Sign up'
}

Screenshots

What areas of the site does it impact?

Homepage email signup form only.