add workflow_dispatch trigger for manual run of tests (#276)

closes #266 

@AlexAxthelm not sure if this would work?

.github/workflows/build-Docker-image-triggers.yml

@@ -6,6 +6,7 @@ on:
     branches: [main]
   schedule:
     - cron: '0 0 * * 1,2,3,4,5'
+  workflow_dispatch:
 
 jobs:
   build_docker_image:
@@ -22,6 +23,7 @@ jobs:
           github.event_name == 'pull_request' && format('{0}{1}','pr', github.event.pull_request.number) ||
           github.event_name == 'schedule' && 'nightly' ||
           github.event_name == 'push' && github.ref_name ||
+          github.event_name == 'workflow_dispatch' && github.ref_name ||
           github.sha 
         }}