Update dotnetcore.yml

.github/workflows/dotnetcore.yml

@@ -14,7 +14,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Setup .NET Core SDK
-      uses: actions/setup-dotnet@v1.5.0
+      uses: actions/setup-dotnet@v1.7.2
     - name: Install dependencies
       run: dotnet restore ./IoTSharp.sln
     - name: Build