github: add manual trigger

.github/workflows/release.yml

@@ -39,10 +39,11 @@ permissions:
 # If there's a prerelease-style suffix to the version, then the release(s)
 # will be marked as a prerelease.
 on:
+  workflow_dispatch:
   pull_request:
   push:
     tags:
-      - '**[0-9]+.[0-9]+.[0-9]+*'
+      - "**[0-9]+.[0-9]+.[0-9]+*"
 
 jobs:
   # Run 'dist plan' (or host) to determine what tasks we need to do