build: fix Build of Compiler-Extension (#4804)

Author: Flash0ver

src/Sentry/Sentry.csproj

@@ -188,8 +188,7 @@
     <ProjectReference Include="..\Sentry.Compiler.Extensions\Sentry.Compiler.Extensions.csproj"
                       OutputItemType="Analyzer"
                       ReferenceOutputAssembly="false"
-                      PrivateAssets="all"
-                      SetTargetFramework="TargetFramework=netstandard2.0" />
+                      PrivateAssets="all" />
   </ItemGroup>
 
   <PropertyGroup>