Implementing interface in PowerShell class does not warn about non-implemented interface members

System Details

System Details Output

### VSCode version: 1.47.3 91899dcef7b8110878ea59626991a18c8a6a1b3e x64

### VSCode extensions:
DavidAnson.vscode-markdownlint@0.36.2
eamodio.gitlens@10.2.2
Fudge.auto-using@0.7.15
jchannon.csharpextensions@1.3.1
k--kato.docomment@0.1.17
mhutchie.git-graph@1.25.0
ms-azuretools.vscode-docker@1.4.1
ms-dotnettools.csharp@1.22.1
ms-vscode-remote.remote-wsl@0.44.4
ms-vscode.cpptools@0.29.0
ms-vscode.powershell@2020.6.0
ms-vscode.powershell-preview@2020.7.0
redhat.vscode-xml@0.13.0
streetsidesoftware.code-spell-checker@1.9.0
zhuangtongfa.material-theme@3.8.5


### PSES version: 2.3.0.0

### PowerShell version:

Name                           Value
----                           -----
PSVersion                      7.1.0-preview.5
PSEdition                      Core
GitCommitId                    7.1.0-preview.5
OS                             Microsoft Windows 10.0.19041
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0

Issue Description

PowerShell class implementing an interface does not create an error if required interface members are not present. There is also not a code action to implement interface.

using namespace System.Management.Automation

class test : IArgumentCompleter
{

}

Expected Behaviour

VS code warns about non-implemented interface members like C#. Code action to implement interface.

Actual Behaviour

VS code does not warn about non-implemented interface members or show code action to resolve.

Attached Logs

Follow the instructions in the troubleshooting docs
about capturing and sending logs.

Start with the PowerShell class example implementing IArgumentCompleter and review how PSScriptAnalyzer reports missing interface members. Use the troubleshooting documentation if diagnostic logs are needed. Done means the editor warns about unimplemented interface members and offers a code action to implement them.