update few project from 4.6.1 to 4.8

Author: zznty

Torch.API/Torch.API.csproj

@@ -7,7 +7,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Torch.API</RootNamespace>
     <AssemblyName>Torch.API</AssemblyName>
-    <TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.8</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <TargetFrameworkProfile />
     <NuGetPackageImportStamp>

Torch.Client.Tests/Torch.Client.Tests.csproj

@@ -7,7 +7,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Torch.Client.Tests</RootNamespace>
     <AssemblyName>Torch.Client.Tests</AssemblyName>
-    <TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.8</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <TargetFrameworkProfile />
     <NuGetPackageImportStamp>

Torch.Client/Torch.Client.csproj

@@ -7,7 +7,7 @@
     <AppDesignerFolder>Properties</AppDesignerFolder>
     <RootNamespace>Torch.Client</RootNamespace>
     <AssemblyName>Torch.Client</AssemblyName>
-    <TargetFrameworkVersion>v4.6.1</TargetFrameworkVersion>
+    <TargetFrameworkVersion>v4.8</TargetFrameworkVersion>
     <FileAlignment>512</FileAlignment>
     <ProjectTypeGuids>{60dc8134-eba5-43b8-bcc9-bb4bc16c2548};{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}</ProjectTypeGuids>
     <WarningLevel>4</WarningLevel>