Merge pull request #349 from fluxcd/label-2.2

Add backport:release/v2.2.x label

Author: matheuscscp

.github/labels.yaml

@@ -13,4 +13,7 @@
 - name: backport:release/v2.1.x
   description: To be backported to release/v2.1.x
   color: '#ffd700'
+- name: backport:release/v2.2.x
+  description: To be backported to release/v2.2.x
+  color: '#ffd700'