IL2CPP crash on launch

[Vale-X]

Describe the bug
The IL2CPP version of builds is crashing shortly after launch and throwing an exception through EOSManager.GetoEOSPlatformInterface. The Mono version of builds work fine, but we cannot use that.

Specifically: Run-Time Check Failure #0 - The value of ESP was not properly saved across a function call. This is usually a result of calling a function declared with one calling convention with a function pointer declared with a different calling convention.

In my attempts to fix this, I have retroactively applied #361 to the 2.3.3 version by applying the same changes to the .tar plugin source, but to no avail. I have previously commented out the code within "OnSteamGUI" in EpicOnlineServicesConfigEditor.cs as that was producing a lot of errors, but since we are not using anything steam related in this case, should not cause any issues.

I was able to reproduce this issue in an empty project, and can upload that here to review if need be.

To Reproduce
Steps to reproduce the behavior:

1. Create empty project in 2020.3.48f1
2. Install EOS plugin for unity 2.3.3
3. Set to compile with IL2CPP
4. Create build
5. Launch build, observe crash.

Desktop (please complete the following information):

• OS: Windows x64
• Standalone Build
• Unity Version: 2020.3.48f1
• Plugin Version: 2.3.3

Additional context
We are using 2.3.3 as it is the latest version compatible with Unity 2020.3.48f1. 3.0.0 onwards targets 2021 and uses a different c# version, which produced a lot of errors in the editor.