fix: Building the SDK on Windows (#2156)

Author: bitsandfoxes

Directory.Build.targets

@@ -186,7 +186,7 @@ Expected to exist:
 
   <!-- Downloads and sets up the Cocoa SDK: dotnet msbuild /t:SetupCocoaSDK src/Sentry.Unity -->
   <Target Name="SetupCocoaSDK"
-      Condition="'$(MSBuildProjectName)' == 'Sentry.Unity'
+      Condition="!$([MSBuild]::IsOSPlatform('Windows')) AND '$(MSBuildProjectName)' == 'Sentry.Unity'
         And (!Exists('$(SentryiOSArtifactsDestination)') Or !Exists('$(SentrymacOSArtifactsDestination)Sentry.dylib'))"
       BeforeTargets="BeforeBuild">
 
@@ -609,7 +609,5 @@ void PrintFailedTests(XElement element)
     <!-- Download overwrites some files that then show up as changed in the IDE, even though there are no changes, e.g. only whitespace -->
     <Message Importance="High" Text="Restoring package-dev/Plugins to the latest git commit" />
     <Exec WorkingDirectory="$(RepoRoot)" Command="git restore package-dev/Plugins" />
-
-
   </Target>
 </Project>