Update CEO references

.vale/handbook/spelling-exceptions.txt

content/handbook/about/handbook-usage.md

content/handbook/ceo/office-of-the-ceo/_index.md

content/handbook/ceo/shadow.md

content/handbook/communication/_index.md

content/handbook/company/amas.md

content/handbook/company/being-a-public-company.md

content/handbook/company/culture/_index.md

content/handbook/company/culture/all-remote/asynchronous.md

...ompany/culture/all-remote/being-a-great-remote-manager.md

...t/handbook/company/culture/all-remote/building-culture.md

content/handbook/company/culture/all-remote/drawbacks.md

...nt/handbook/company/culture/all-remote/getting-started.md

...ent/handbook/company/culture/all-remote/handbook-first.md

...ent/handbook/company/culture/all-remote/head-of-remote.md

content/handbook/company/culture/all-remote/hiring.md

content/handbook/company/culture/all-remote/hybrid-remote.md

content/handbook/company/culture/all-remote/in-person.md

...book/company/culture/all-remote/informal-communication.md

content/handbook/company/culture/all-remote/internship.md