ci: Revert minimum E2E timeout to 20 minutes (#27827)

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## **Description**

Reverts the minimum E2E timeout back to 20 minutes to unblock merges to
`develop` while we investigate why E2E's have slowed down dramatically.

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.circleci/scripts/test-run-e2e-timeout-minutes.ts

@@ -2,7 +2,7 @@ import { filterE2eChangedFiles } from '../../test/e2e/changedFilesUtil';
 
 const changedOrNewTests = filterE2eChangedFiles();
 
-//15 minutes, plus 3 minutes for every changed file, up to a maximum of 30 minutes
-const extraTime = Math.min(15 + changedOrNewTests.length * 3, 30);
+// 20 minutes, plus 3 minutes for every changed file, up to a maximum of 30 minutes
+const extraTime = Math.min(20 + changedOrNewTests.length * 3, 30);
 
 console.log(extraTime);