Import shell integration module

[andyleejordan]

Per PowerShell/vscode-powershell#5217

[andyleejordan]

@andys-macbook-air ~/src/vscode-powershell/examples module ≡
> gmo

ModuleType Version    PreRelease Name                                ExportedCommands
---------- -------    ---------- ----                                ----------------
Manifest   7.0.0.0               Microsoft.PowerShell.Management     {Add-Content, Clear-Content,…
Manifest   7.0.0.0               Microsoft.PowerShell.Utility        {Add-Member, Add-Type, Clear…
Script     1.1.0                 posh-git                            {Add-PoshGitToProfile, Expan…
Script     0.2.0                 PowerShellEditorServices.Commands   {Clear-Host, ConvertFrom-Scr…
Script     2.4.1      beta1      PSReadLine                          {Get-PSReadLineKeyHandler, G…
Script     0.0                   shellIntegration                    {Compress-Completions, Send-…