docs: harmonize on injectDocumentDomain removal in future version (#6154)

Author: MikeMcC399

docs/app/references/configuration.mdx

@@ -599,7 +599,7 @@ or [`component`](#component) testing-specific options.
 
 ### injectDocumentDomain
 
-This option is <Badge type="caution">deprecated</Badge>, and will be removed in Cypress. 15
+This option is <Badge type="caution">deprecated</Badge>, and will be removed in a future version of Cypress.
 
 Set this configuration option to `true` to instruct Cypress to
 [inject document.domain](/app/guides/cross-origin-testing#What-Cypress-does-under-the-hood)
@@ -608,7 +608,7 @@ between subdomains](/app/guides/cross-origin-testing), but comes with compatibil
 caveats for some sites.
 
 This configuration option is provided to ease the transition between `cy.origin()`'s behavior
-in Cypress 13 and the default behavior in Cypress 14. It will be removed in a future version of Cypress.
+in Cypress 13 and the default behavior in Cypress 14.
 [Read the Cypress 14 migration guide](/app/references/migration-guide#Migrating-to-Cypress-140) to understand how to update your tests to remove
 the need to set this flag.
 

docs/app/references/migration-guide.mdx

@@ -83,8 +83,8 @@ is set to true, `cy.origin()` will not be required to navigate between origins,
 <Icon name="exclamation-triangle" /> If `injectDocumentDomain` is set to `true`,
 Cypress will warn that this option is deprecated.
 
-<Icon name="exclamation-triangle" /> `injectDocumentDomain` will be removed in Cypress
-15.
+<Icon name="exclamation-triangle" /> `injectDocumentDomain` will be removed in a
+future version of Cypress.
 
 <Icon name="exclamation-triangle" /> Setting `injectDocumentDomain` to `true` may
 cause certain sites to stop working in Cypress. Please read the [configuration notes](/app/references/configuration#injectDocumentDomain)