Fix getheaders regression with open_url in Scaleway dynamic inventory (#48671)

* Fix regression

* Improve changelog fragment

changelogs/fragments/scaleway-getheaders.yaml

@@ -0,0 +1,3 @@
+---
+bugfixes:
+- scaleway inventory plugin - Fix response.getheaders regression (https://github.com/ansible/ansible/pull/48671)

lib/ansible/plugins/inventory/scaleway.py

@@ -113,7 +113,7 @@ def _fetch_information(token, url):
         except KeyError:
             raise AnsibleError("Incorrect format from the Scaleway API response")
 
-        link = response.getheader('Link')
+        link = response.headers['Link']
         if not link:
             return results
         relations = parse_pagination_link(link)