Fix migration issues

BepInEx.IL2CPP/BepInEx.IL2CPP.csproj

@@ -39,6 +39,7 @@
     <Reference Include="UnityEngine.CoreModule-IL2CPP">
       <HintPath>..\lib\UnityEngine.CoreModule-IL2CPP.dll</HintPath>
       <Private>False</Private>
+      <Aliases>il2cpp</Aliases>
     </Reference>
   </ItemGroup>
   <ItemGroup>

BepInEx.Patcher/BepInEx.Patcher.csproj

@@ -17,17 +17,10 @@
     <StartupObject>BepInEx.Patcher.Program</StartupObject>
   </PropertyGroup>
   <Import Project="$(SolutionDir)\packages\ILRepack.Lib.MSBuild.Task.2.0.16.1\build\ILRepack.Lib.MSBuild.Task.targets" Condition="Exists('$(SolutionDir)\packages\ILRepack.Lib.MSBuild.Task.2.0.16.1\build\ILRepack.Lib.MSBuild.Task.targets')" />
-  <Target Name="EnsureNuGetPackageBuildImports" BeforeTargets="PrepareForBuild">
-    <PropertyGroup>
-      <ErrorText>This project references NuGet package(s) that are missing on this computer. Use NuGet Package Restore to download them.  For more information, see http://go.microsoft.com/fwlink/?LinkID=322105. The missing file is {0}.</ErrorText>
-    </PropertyGroup>
-    <Error Condition="!Exists('$(SolutionDir)\packages\ILRepack.2.0.16\build\ILRepack.props')" Text="$([System.String]::Format('$(ErrorText)', '..\packages\ILRepack.2.0.16\build\ILRepack.props'))" />
-    <Error Condition="!Exists('$(SolutionDir)\packages\ILRepack.Lib.MSBuild.Task.2.0.16.1\build\ILRepack.Lib.MSBuild.Task.targets')" Text="$([System.String]::Format('$(ErrorText)', '$(SolutionDir)\packages\ILRepack.Lib.MSBuild.Task.2.0.16.1\build\ILRepack.Lib.MSBuild.Task.targets'))" />
-  </Target>
   <ItemGroup>
     <PackageReference Include="ILRepack" Version="2.0.16" />
     <PackageReference Include="ILRepack.Lib.MSBuild.Task" Version="2.0.16.1" />
-    <PackageReference Include="Mono.Cecil" Version="0.10.3" />
+    <PackageReference Include="Mono.Cecil" Version="0.10.4" />
   </ItemGroup>
   <ItemGroup>
     <Reference Include="Mono.Cecil, Version=0.10.3.0, Culture=neutral, PublicKeyToken=50cebf1cceb9d05e, processorArchitecture=MSIL">