Update changelogs from fern repo (#875)

Co-authored-by: Swimburger <[email protected]>

Author: fern-support

fern/products/sdks/overview/typescript/changelog/2025-09-17.mdx

@@ -1,3 +1,8 @@
+## 2.13.0
+**`(feat):`** Use Vitest instead of Jest for running tests. 
+Enable Vitest by setting `testFramework` to `vitest` in the `config` of your generator configuration.
+
+
 ## 2.12.3
 **`(chore):`** Updated retry strategy; in particular, don't jitter for `retry-after` header.