dotnet format reports warning when project output dlls are not present

### Describe the bug
We run dotnet format like this: --no-restore --verbosity diagnostic --verify-no-changes to check for formatting style prior to building. (We do a restore prior to dotnet format)
Unfortunately, we get the following error (warning as error): Msbuild failed when processing the file 'XXX.csproj' with message: Unknown build error, 'Could not find a part of the path XXX.dll

### To Reproduce
This happens on cleaned/freshly checkout repos.

### Exceptions (if any)
If the repo has been build previously no errors are reported, as the output files exists.