Make e2e run on 6.x branch too.
diff --git a/.github/workflows/e2e.yaml b/.github/workflows/e2e.yaml
index effd6f3..9ac777e 100644
--- a/.github/workflows/e2e.yaml
+++ b/.github/workflows/e2e.yaml
@@ -21,6 +21,7 @@
   push:
     branches:
       - master
+      - 6.x
     tags:
       - 'v*'