Update uwp package to v5.2.6 in unit test projects

Author: dhei

unittest/Microsoft.WindowsAzure.MobileServices.SQLiteStore.UWP.Test/project.json

@@ -1,6 +1,6 @@
 {
   "dependencies": {
-    "Microsoft.NETCore.UniversalWindowsPlatform": "5.2.3"
+    "Microsoft.NETCore.UniversalWindowsPlatform": "5.2.6"
   },
   "frameworks": {
     "uap10.0": {}

unittest/Microsoft.WindowsAzure.MobileServices.Test/Microsoft.WindowsAzure.Mobile.Test.csproj

@@ -16,7 +16,7 @@
      <Reference Include="System.Net.Http" />
    </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'uap10.0' ">
-    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="5.2.3" />
+    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="5.2.6" />
   </ItemGroup>
 
   <PropertyGroup Condition=" '$(TargetFramework)' == 'MonoAndroid70' ">

unittest/Microsoft.WindowsAzure.MobileServices.TestFramework/Microsoft.WindowsAzure.Mobile.TestFramework.csproj

@@ -18,7 +18,7 @@
      <PackageReference Include="MSBuild.Sdk.Extras" Version="1.0.5" PrivateAssets="All" />
   </ItemGroup>
   <ItemGroup Condition=" '$(TargetFramework)' == 'uap10.0' ">
-    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="5.2.3" />
+    <PackageReference Include="Microsoft.NETCore.UniversalWindowsPlatform" Version="5.2.6" />
   </ItemGroup>
   <Import Project="$(MSBuildSDKExtrasTargets)" Condition="Exists('$(MSBuildSDKExtrasTargets)')" />
 </Project>

unittest/Microsoft.WindowsAzure.MobileServices.UWP.Test/project.json

@@ -1,6 +1,6 @@
 {
   "dependencies": {
-    "Microsoft.NETCore.UniversalWindowsPlatform": "5.2.3"
+    "Microsoft.NETCore.UniversalWindowsPlatform": "5.2.6"
 
   },
   "frameworks": {