Delete unused workflow

.github/workflows/main.yml

@@ -1,17 +0,0 @@
-name: Deploy
-
-on:
-  push:
-    branches:
-      - master
-
-jobs:
-  build:
-    runs-on: ubuntu-latest
-    steps:
-      - uses: actions/checkout@v2
-      - uses: akhileshns/heroku-deploy@v3.3.6
-        with:
-          heroku_api_key: ${{secrets.HEROKU_API_KEY}}
-          heroku_app_name: "sj-staffmanagement"
-          heroku_email: ${{secrets.HEROKU_EMAIL}}