Exec Command UseCommandProcessor = "True" is missing cmd.exe

When setting `UseCommandProcessor = "True"` in an `

bin\


VerilogIssue
{C32098DE-768D-4521-8C70-119A087D9407}


.\build\vs-prog.bat

InstallBuildDependencies;

```

Directory contents:
```
(none)
```

### Expected behavior

As noted in the [documentation](https://docs.microsoft.com/en-us/visualstudio/msbuild/exec-task?view=vs-2019), setting [UseCommandProcessor](https://docs.microsoft.com/en-us/dotnet/api/microsoft.build.utilities.tooltask.usecommandprocessor?view=netframework-4.8) = "true" should:

>When set to true, this task creates a batch file for the command line and executes it by using the command-processor instead of executing the command directly.

First, no batch file is created... instead it appears there's an attempt to wrap with just `cmd.exe`.

Further, as shown in the example below, the `cmd.exe` is missing, and should should have been added like this:
```
cmd.exe /Q /D /C C:\Users\gojimmypi\AppData\Local\Temp\tmp8e500fe3f5f24fbd896f954d39d199f5.exec.cmd
```

### Actual behavior
Note in particular the 7th line:
```
1> C:\Users\gojimmypi\source\repos\Verilog45\Verilog45>/Q /D /C ....
```
from the full build output:
```
1>------ Build started: Project: VerilogIssue, Configuration: Debug Any CPU ------
1>Build started 6/21/2020 11:41:07 AM.
1>Build:
1> ping 192.168.1.1
1> ping 192.168.1.1
1>
1> C:\Users\gojimmypi\source\repos\Verilog45\Verilog45>/Q /D /C C:\Users\gojimmypi\AppData\Local\Temp\tmp8e500fe3f5f24fbd896f954d39d199f5.exec.cmd
1> '/Q' is not recognized as an internal or external command,
1> operable program or batch file.
1>C:\Users\gojimmypi\source\repos\Verilog45\Verilog45\VerilogIssue.csproj(20,5): error MSB3073: The command "ping 192.168.1.1" exited with code 1.
1>
1>Build FAILED.
1>
1>"C:\Users\gojimmypi\source\repos\Verilog45\Verilog45\VerilogIssue.csproj" (Build target) (1) ->
1>(Build target) ->
1> C:\Users\gojimmypi\source\repos\Verilog45\Verilog45\VerilogIssue.csproj(20,5): error MSB3073: The command "ping 192.168.1.1" exited with code 1.
1>
1> 0 Warning(s)
1> 1 Error(s)
1>
1>Time Elapsed 00:00:00.08
========== Build: 0 succeeded, 1 failed, 0 up-to-date, 0 skipped ==========

```
### Environment data
`msbuild /version` output:

```
C:\Program Files (x86)\Microsoft Visual Studio\2019\Enterprise>msbuild /version
Microsoft (R) Build Engine version 16.5.0+d4cbfca49 for .NET Framework
Copyright (C) Microsoft Corporation. All rights reserved.

16.5.0.12403
```

OS info:

```
Microsoft Windows [Version 10.0.18363.900]
```

If applicable, version of the tool that invokes MSBuild (Visual Studio, dotnet CLI, etc):

```
Microsoft Visual Studio Enterprise 2019 (3)
Version 16.6.1
VisualStudio.16.Release/16.6.1+30128.74
Microsoft .NET Framework
Version 4.8.03752

Installed Version: Enterprise
```

edit: this is related to https://github.com/gojimmypi/VerilogLanguageExtension/pull/25#issuecomment-640307560