Update workflow dispatch rules in dotnet.yml

Author: Matthiee

.github/workflows/dotnet.yml

@@ -1,10 +1,13 @@
 name: .NET
 
 on:
+  workflow_dispatch:
   push:
     branches: [ master ]
   pull_request:
     branches: [ master ]
+  release:
+    types: [released]
 
 jobs:
   build: