build(dotnet): upgrade iOS target framework to .NET 9 (#447)

Author: CBenoit

ffi/dotnet/Devolutions.Picky/Devolutions.Picky.Build.props

@@ -1,7 +1,7 @@
 <Project>
   <PropertyGroup>
-    <TargetFrameworks>netstandard2.0;net8.0-ios</TargetFrameworks>
-     <SupportedOSPlatformVersion Condition="'$(TargetFramework)' == 'net8.0-ios'">12.1</SupportedOSPlatformVersion>
+    <TargetFrameworks>netstandard2.0;net9.0-ios</TargetFrameworks>
+     <SupportedOSPlatformVersion Condition="'$(TargetFramework)' == 'net9.0-ios'">12.1</SupportedOSPlatformVersion>
   </PropertyGroup>
 
   <ItemGroup>
@@ -115,4 +115,4 @@
     <Content Include="Devolutions.Picky.targets" PackagePath="build/Devolutions.Picky.targets" Pack="true" />
     <Content Include="Devolutions.Picky.props" PackagePath="build/Devolutions.Picky.props" Pack="true" />
   </ItemGroup>
-</Project>
+</Project>