Add experimentalSessionAndOrigin removed comment to origin video (#6158)

Author: MikeMcC399

docs/api/commands/origin.mdx

@@ -367,6 +367,9 @@ Cypress.Commands.add('login', (username, password) => {
 In this video we walk through how to test multiple origins in a single test. We
 also look at how to use the `cy.session()` command to cache session information
 and reuse it across tests.
+The configuration option `experimentalSessionAndOrigin`, mentioned in the video, is not used
+since [Cypress 12.0.0](https://docs.cypress.io/app/references/changelog#12-0-0)
+and the associated functionality is enabled by default.
 
 ## Notes