MPC Generate Error when use photon-quantum define classs that contains an FP field

[3wz]

Bug description

When using Photon-Quantum to write configuration classes, defining an FP field inside and then attempting to generate using MPC results in errors.

Repro steps

download the unity project zip, then open it by unity3d, then you can see the errors, you can generate it again.
MessagePackBug2.zip

• Version used:
• Runtime: (e.g. .NET Framework, .NET Core, Unity, mono, etc.)
• dotnet version: 8.0.202
• mpc version: 2.5.140+eefc9079d1