Update changelogs from fern repo (#5419)

Co-authored-by: dsinghvi <10870189+dsinghvi@users.noreply.github.com>

Author: fern-support

fern/products/cli-api-reference/cli-changelog/2026-05-07.mdx

@@ -1,3 +1,9 @@
+## 5.18.1
+**`(fix):`** Fix GitHub Enterprise support for self-hosted SDK generation. Octokit API calls
+(signed commits, PR creation, ref updates) now use the correct GHE API base URL
+derived from the repository URI instead of always hitting api.github.com.
+
+
 ## 5.18.0
 **`(feat):`** Add `fern schema [name]` command (CLI v2) that emits a JSON Schema for
 `fern.yml`. Running `fern schema` with no argument prints the full schema;