[DNS] Replace occurrences of subdomain with record terminology

[RebeccaTamachiro]

Summary

Closes #25798

[github-actions]

This PR requires additional review attention because it affects the following areas:

Partials

This PR updates partial files, which are pieces of content used across multiple files in our Render component.

• dns/create-subdomain-record - view affected files
• dns/dns-scan-procedure - view affected files

[github-actions]

This pull request requires reviews from CODEOWNERS as it changes files that match the following patterns:

Pattern	Owners
/src/content/docs/dns/	@RebeccaTamachiro, @cloudflare/pcx-technical-writing
/src/content/docs/fundamentals/	@dcpena, @cloudflare/pcx-technical-writing
*	@cloudflare/pcx-technical-writing

[github-actions]

Preview URL: https://012c13e0.preview.developers.cloudflare.com
Preview Branch URL: https://rebecca-dns-subdomain-terminology-review.preview.developers.cloudflare.com

Files with changes (up to 15)

Original Link	Updated Link
https://developers.cloudflare.com/dns/manage-dns-records/how-to/round-robin-dns/	https://rebecca-dns-subdomain-terminology-review.preview.developers.cloudflare.com/dns/manage-dns-records/how-to/round-robin-dns/
https://developers.cloudflare.com/fundamentals/manage-domains/redirect-domain/	https://rebecca-dns-subdomain-terminology-review.preview.developers.cloudflare.com/fundamentals/manage-domains/redirect-domain/