ci: enable legacy release (#447)

diff --git a/.github/workflows/release.yaml b/.github/workflows/release.yaml
index 877f501..51f4c17 100644
--- a/.github/workflows/release.yaml
+++ b/.github/workflows/release.yaml
@@ -4,6 +4,7 @@
   push:
     branches:
       - master
+      - legacy
 
 jobs:
   release: