[test/TD-10790]<test>(connector):update .csproj

tests/system-test/3-connectors/c#/TDengineDriver/TDengineDriver.csproj

-<Project Sdk="Microsoft.NET.Sdk">
-
-  <PropertyGroup>
-    <TargetFramework>net6.0</TargetFramework>
-    <ImplicitUsings>enable</ImplicitUsings>
-    <Nullable>enable</Nullable>
-  </PropertyGroup>
-
-</Project>
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <TargetFramework>net5.0</TargetFramework>
+  </PropertyGroup>
+
+</Project>

tests/system-test/3-connectors/c#/test.sh

@@ -27,7 +27,7 @@ dotnet run --project TDengineTest/TDengineTest.csproj
 dotnet run --project schemaless/schemaless.csproj
 
 cd ${WKC}/tests/system-test/3-connectors/c#/stmtfunction
-dotnet run
+dotnet run || exit 1
 
 cd ${WKC}/tests/examples/C#/taosdemo
 dotnet build -c Release