Dashboard labels corrected in docs

Patch Changes

• Correct two Dashboard labels referenced in the instance restrictions documentation. blockDisposableEmailDomains bolded "Block sign-ups that use disposable email domains", but the toggle in the Clerk Dashboard is "Block sign-ups that use disposable email addresses". ignoreDotsForGmailAddresses bolded "Ignore dots for Gmail addresses" as a Dashboard toggle, but no such control exists — the wording now matches the equivalent comment on UpdateRestrictionsParams. Property names are unchanged. (#9253) by @manovotny