Fix tests for CI

Author: chkr1011

Directory.Build.props

@@ -11,6 +11,7 @@
         <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
         <EnforceCodeStyleInBuild>false</EnforceCodeStyleInBuild>
         <ImplicitUsings>enable</ImplicitUsings>
+        <Nullable>disable</Nullable>
 
         <NeutralLanguage>en-US</NeutralLanguage>
         <TreatWarningsAsErrors>true</TreatWarningsAsErrors>
@@ -24,10 +25,6 @@
         <AnalysisLevel>latest</AnalysisLevel>
         <AnalysisMode>recommended</AnalysisMode>
         <AnalysisModeStyle>default</AnalysisModeStyle>
-
-        <TestingPlatformShowTestsFailure>true</TestingPlatformShowTestsFailure>
-        <TestingPlatformDotnetTestSupport>true</TestingPlatformDotnetTestSupport>
-        <EnableMSTestRunner>true</EnableMSTestRunner>
     </PropertyGroup>
 
     <PropertyGroup Condition="'$(GITHUB_ACTIONS)' == 'true'">

Source/MQTTnet.TestApp/MQTTnet.TestApp.csproj

@@ -2,7 +2,6 @@
 
     <PropertyGroup>
         <OutputType>Exe</OutputType>
-        <DebugType>Full</DebugType>
         <IsPackable>false</IsPackable>
     </PropertyGroup>