PSModulePath mutated during script changes

Issue Description

PSModulePath is modified with every edit to a file.

Steps to repo

Run this in the PSIC:

$env:PSModulePath
$env:PSModulePath = "C:\Users\tyleonha\.vscode-insiders\extensions\ms-vscode.powershell-preview-2019.5.0\modules"
$env:PSModulePath

Verify it changed.

Now make a single edit to a script and check the PSModulePath once more... It should look like:

C:\Users\tyleonha\Documents\PowerShell\Modules;C:\Users\tyleonha.vscode-insiders\extensions\ms-vscode.powershell-preview-2019.5.0\modules;C:\Program Files\PowerShell\Modules;c:\program files\powershell\7-preview\Modules;C:\Windows\system32\WindowsPowerShell\v1.0\Modules

Apparently, the PSModulePath is updated every time you spin up a Runspace so I wonder if we're doing something like that...

Attached Logs

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Environment Information

Visual Studio Code

PowerShell Information

Visual Studio Code Extensions

Empieza reproduciendo el problema en la PowerShell Integrated Console (PSIC): registra PSModulePath, edita un script y vuelve a compararlo. Después, rastrea la creación y la inicialización de runspaces, ya que el issue indica que iniciar un runspace puede actualizar PSModulePath. Se considera terminado cuando editar un script ya no modifica inesperadamente el PSModulePath existente.