dnx fails to pass arguments properly when they contain an ampersand (&)

### Describe the bug
When running a tool via `dnx` (via pwsh) that requires an argument containing an ampersand, the argument is incorrectly split on the & and the text following it is passed to `cmd` instead.

### To Reproduce

# This works fine
`dnx dotnetsay works`

# This fails
`dnx dotnetsay "bro&ken"`

# As does this
`dnx dotnetsay 'bro&ken'`

# Calling dotnet tool exec instead is fine
`dotnet tool exec dotnetsay 'bro&ken'`

# Using `--%` is also ok
`dnx dotnetsay --% "bro&ken"`

### Exceptions (if any)

The output from one of the broken commands:

```
> dnx dotnetsay "bro&ken"

bro
__________________
\
\
....
....'
....
..........
.............'..'..
................'..'.....
.......'..........'..'..'....
........'..........'..'..'.....
.'....'..'..........'..'.......'.
.'..................'... ......
. ......'......... .....
. ......
.. . .. ......
.... . .......
...... ....... ............
................ ......................
........................'................
......................'..'...... .......
.........................'..'..... .......
........ ..'.............'..'.... ..........
..'..'... ...............'....... ..........
...'...... ...... .......... ...... .......
........... ....... ........ ......
....... '...'.'. '.'.'.' ....
....... .....'.. ..'.....
.. .......... ..'........
............ ..............
............. '..............
...........'.. .'.'............
............... .'.'.............
.............'.. ..'..'...........
............... .'..............
......... ..............
.....

'ken' is not recognized as an internal or external command,
operable program or batch file.
```

It's clear that everything after the `&` is being passed to `cmd`.

### Further technical details
details of dotnet --info

> dotnet --info
.NET SDK:
Version: 10.0.102
Commit: 4452502459
Workload version: 10.0.100-manifests.6d969a7e
MSBuild version: 18.0.7+445250245

Runtime Environment:
OS Name: Windows
OS Version: 10.0.26100
OS Platform: Windows
RID: win-x64
Base Path: C:\Program Files\dotnet\sdk\10.0.102\

.NET workloads installed:
There are no installed workloads to display.
Configured to use workload sets when installing new manifests.
No workload sets are installed. Run "dotnet workload restore" to install a workload set.

Host:
Version: 10.0.2
Architecture: x64
Commit: 4452502459

.NET SDKs installed:
10.0.100 [C:\Program Files\dotnet\sdk]
10.0.102 [C:\Program Files\dotnet\sdk]

.NET runtimes installed:
Microsoft.AspNetCore.App 8.0.23 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 10.0.0 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.AspNetCore.App 10.0.2 [C:\Program Files\dotnet\shared\Microsoft.AspNetCore.App]
Microsoft.NETCore.App 8.0.23 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 9.0.12 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 10.0.0 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.NETCore.App 10.0.2 [C:\Program Files\dotnet\shared\Microsoft.NETCore.App]
Microsoft.WindowsDesktop.App 8.0.23 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 9.0.12 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 10.0.0 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]
Microsoft.WindowsDesktop.App 10.0.2 [C:\Program Files\dotnet\shared\Microsoft.WindowsDesktop.App]

Other architectures found:
x86 [C:\Program Files (x86)\dotnet]
registered at [HKLM\SOFTWARE\dotnet\Setup\InstalledVersions\x86\InstallLocation]

Environment variables:
DOTNET_SYSTEM_NET_SECURITY_NOREVOCATIONCHECKBYDEFAULT [true]

global.json file:
Not found

Learn more:
https://aka.ms/dotnet/info

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https://aka.ms/dotnet/download

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Windows Terminal PowerShell session.