Support a manual trigger on CI workflow
diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1d29cc3..9b496eb 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -3,6 +3,7 @@
 on:
   push:
   pull_request:
+  workflow_dispatch:
   schedule: [cron: "40 1 * * *"]
 
 permissions:
diff --git a/.github/workflows/site.yml b/.github/workflows/site.yml
index 09382b7..1f9a695 100644
--- a/.github/workflows/site.yml
+++ b/.github/workflows/site.yml
@@ -7,6 +7,7 @@
     paths:
       - book/**
       - .github/workflows/site.yml
+  workflow_dispatch:
 
 jobs:
   deploy: