Add release note category "API changes"

[skip ci]

.github/PULL_REQUEST_TEMPLATE.md

@@ -23,6 +23,7 @@
 Changelog Category (reviewers may add a label for the release notes):
 
 - [x] User facing changes
+- [ ] API changes (V0, V1 or DFC)
 - [ ] Technical changes only
 - [ ] Feature toggled
 

.github/release.yml

@@ -5,9 +5,13 @@ changelog:
         - '*'
       exclude:
         labels:
+          - api changes
           - dependencies
           - feature toggled
           - technical changes only
+    - title: "API changes ⚠️"
+      labels:
+        - api changes
     - title: "Features under construction 🚧"
       labels:
         - feature toggled