.github: allow workflow to be triggered manually

Signed-off-by: Lucas Servén Marín <lserven@gmail.com>

.github/workflows/ci.yml

@@ -7,6 +7,7 @@ on:
     branches: [ master ]
   schedule:
   - cron:  '0 0 * * *'
+  workflow_dispatch:
 
 jobs: