Update changelogs from fern repo (#887)

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

Author: fern-support

fern/products/sdks/overview/go/changelog/2025-09-18.mdx

@@ -1,3 +1,7 @@
+## 1.12.0
+**`(feat):`** Add support for custom sections in the README.md via `customSections` config option.
+
+
 ## 1.11.3
 **`(chore):`** Update retrier to match strategy with TS SDKs exactly; in particular,
 don't use jitter on `retry-after` and instead respect it exactly.