Convert NewsletterForm to TypeScript (#19511)

...rc/metabase/auth/components/GoogleButton/GoogleButton.tsx

frontend/src/metabase/components/Input.jsx

frontend/src/metabase/components/Input/Input.styled.tsx

frontend/src/metabase/components/Input/Input.tsx

frontend/src/metabase/components/Input/index.ts

frontend/src/metabase/components/NewsletterForm.jsx

...metabase/setup/components/CompletedStep/CompletedStep.tsx

...etup/components/CompletedStep/CompletedStep.unit.spec.tsx

...setup/components/NewsletterForm/NewsletterForm.styled.tsx

...tabase/setup/components/NewsletterForm/NewsletterForm.tsx

...up/components/NewsletterForm/NewsletterForm.unit.spec.tsx

...end/src/metabase/setup/components/NewsletterForm/index.ts

...metabase/setup/containers/CompletedStep/CompletedStep.tsx

...tabase/setup/containers/NewsletterForm/NewsletterForm.tsx

...end/src/metabase/setup/containers/NewsletterForm/index.ts

frontend/src/metabase/setup/selectors.ts

frontend/src/metabase/setup/utils.ts