Update main.yml (#190)

Update pipeline to use .NET 8.

Author: AaronRobinsonMSFT

.github/workflows/main.yml

@@ -21,7 +21,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v3
       with:
-        dotnet-version: '7.0.x'
+        dotnet-version: '8.0.x'
         dotnet-quality: 'ga'
     - name: Build Product and Package
       run: dotnet build src/create_package.proj -c ${{ matrix.flavor }}
@@ -51,7 +51,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v3
       with:
-        dotnet-version: '7.0.x'
+        dotnet-version: '8.0.x'
         dotnet-quality: 'ga'
     - name: Build Product and Package
       run: dotnet build src\create_package.proj -c ${{ matrix.flavor }}
@@ -76,7 +76,7 @@ jobs:
     - name: Setup .NET
       uses: actions/setup-dotnet@v3
       with:
-        dotnet-version: '7.0.x'
+        dotnet-version: '8.0.x'
         dotnet-quality: 'ga'
     - name: Build Product and Package
       run: dotnet build src/create_package.proj -c  ${{ matrix.flavor }}