Add release trigger for plugin pipeline

.github/workflows/build.yml

@@ -1,10 +1,9 @@
 on:
-  pull_request:
-    branches:
-      - master
   push:
     branches:
       - master
+  repository_dispatch:
+    types: [release_event]
 
 jobs:
   build-and-push-base:
@@ -55,4 +54,4 @@ jobs:
       network: "host"
     secrets: inherit
 
-
+