Repository: godot
Issue: Mono Build fails with "Missing required property 'OutputPath' for project type 'PackageReference'."
Labels: bug,platform:windows,confirmed,topic:dotnet

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**Godot version:**
v3.2.2.rc1.mono.official

**OS/device including version:**
Windows 10

**Issue description:**
Cannot build any Mono Project with MSBuild (Mono). Projects build without a problem using MSBuild (VS Build Tools).

**Steps to reproduce:**
- Try to build a Mono project with Godot_v3.2.1-stable_mono_win64.exe using MSBuild (Mono)

**Minimal reproduction project:**
[Test Mono RC1.zip](https://github.com/godotengine/godot/files/4787739/Test.Mono.RC1.zip)

Console Output:
```
Godot Engine v3.2.2.rc1.mono.official - https://godotengine.org
OpenGL ES 3.0 Renderer: Intel(R) HD Graphics 4600

Mono: Logfile is: C:\Users\Marcel\AppData\Roaming/Godot/mono/mono_logs/2020_06_16 17.16.11 (15180).txt
Editing project: C:/Users/Marcel/Downloads/Godot/Test Mono RC1 (C:::Users::Marcel::Downloads::Godot::Test Mono RC1)
Godot Engine v3.2.2.rc1.mono.official - https://godotengine.org
OpenGL ES 3.0 Renderer: Intel(R) HD Graphics 4600

Mono: Logfile is: C:\Users\Marcel\AppData\Roaming/Godot/mono/mono_logs/2020_06_16 17.16.14 (8508).txt
Running: "C:\Program Files\Mono\bin\msbuild.bat" "C:/Users/Marcel/Downloads/Godot/Test Mono RC1/Test Mono RC1.sln" /v:normal /t:Restore,Build "/p:Configuration=Debug" "/l:GodotTools.BuildLogger.GodotBuildLogger,C:\Users\Marcel\Downloads\Godot\Godot_v3.2.2-rc1_mono_win64\GodotSharp\Tools\GodotTools.BuildLogger.dll;C:\Users\Marcel\AppData\Roaming/Godot/mono/build_logs\adeb49de002905ec5b4f1c77aaf06cf7_Debug" /p:GodotDefineConstants=\"GODOT_WINDOWS;GODOT_64;\"
Microsoft (R) Build Engine version 16.5.0-ci for Mono
Copyright (C) Microsoft Corporation. All rights reserved.

Build started 16/06/2020 17:16:20.
Project "C:\Users\Marcel\Downloads\Godot\Test Mono RC1\Test Mono RC1.sln" on node 1 (Restore;Build target(s)).
ValidateSolutionConfiguration:
  Building solution configuration "Debug|Any CPU".
ERROR: call_build: An EditorPlugin build callback failed.
   At: editor/editor_node.cpp:5276
```

Build Log:
```
Project "Test Mono RC1.sln" (Restore;Build target(s)):
	Message: Building solution configuration "Debug|Any CPU".
	Project "Test Mono RC1.csproj" (Restore target(s)):
		Project "Test Mono RC1.csproj" (_IsProjectRestoreSupported target(s)):
		Done building project "Test Mono RC1.csproj".
		Project "Test Mono RC1.csproj" (_GenerateRestoreProjectPathWalk target(s)):
		Done building project "Test Mono RC1.csproj".
		Project "Test Mono RC1.csproj" (_IsProjectRestoreSupported target(s)):
		Done building project "Test Mono RC1.csproj".
		Project "Test Mono RC1.csproj" (_GenerateRestoreGraphProjectEntry target(s)):
		Done building project "Test Mono RC1.csproj".
		Project "Test Mono RC1.csproj" (_GenerateProjectRestoreGraph target(s)):
		Done building project "Test Mono RC1.csproj".
		C:\Program Files\Mono\lib\mono\msbuild\15.0\bin\NuGet.targets(124,5): error : Invalid restore input. Missing required property 'OutputPath' for project type 'PackageReference'. Input files: C:\Users\Marcel\Downloads\Godot\Test Mono RC1\Test Mono RC1.csproj. [C:\Users\Marcel\Downloads\Godot\Test Mono RC1\Test Mono RC1.csproj]
```

Possibly related to #36361.