Add API v4.91.0 Changelog

Author: bbiggerr

src/content/changelog/4-91-0-2021-05-03.md

@@ -0,0 +1,18 @@
+---
+title: '4.91.0: 2021-05-03'
+date: 2021-05-03T04:00:00.000Z
+version: 4.91.0
+changelog:
+  - API
+---
+
+### Changed
+
+- The descriptions for the following Images endpoints were updated to improve accuracy and clarity:
+  - Images List ([GET /images](https://www.linode.com/docs/api/images/#images-list))
+  - Image Create ([POST /images](https://www.linode.com/docs/api/images/#image-create))
+  - Image Upload ([POST /images/upload](https://www.linode.com/docs/api/images/#image-upload))
+
+### Fixed
+
+- A bug was fixed that caused 500 errors to return when empty request body or strings were submitted to the Firewall Rules Update ([PUT /networking/firewalls/{firewallId}/rules](https://www.linode.com/docs/api/networking/#firewall-rules-update)) beta endpoint. An error is now returned instead.