`workflow_dispatch`を使う。
```yaml
on: workflow_dispatch
```
パラメータも指定できる。
```yaml
name: Manually triggered workflow
on:
workflow_dispatch:
inputs:
name:
description: 'Person to greet'
required: true
default: 'Mona the Octocat'
home:
description: 'location'
required: false
default: 'The Octoverse'
jobs:
say_hello:
runs-on: ubuntu-latest
steps:
- run: |
echo "Hello ${{ github.event.inputs.name }}!"
echo "- in ${{ github.event.inputs.home }}!"
```