GitHub actions not running in background when shell is cmd

Question

I have a scenario where in, I want to run the server in the background and run the unit tests that are dependent on the server. Problem is, if I remove shell=cmd and run, it runs fine in background but uses Windows Powershell as the default shell. In this case it clearly shows, running as background task.

But I don't want that. I want the shell to be cmd. When I specify shell=cmd, the server operation just blocks.

I have created a sample project.

These are my entire actions:

name: Test unit tests CI

on:
  push:
    branches: [ "main" ]
  pull_request:
    branches: [ "main" ]


jobs:
  build:

    runs-on: windows-2022

    steps:
    - uses: actions/checkout@v3

    - name: setup Msbuild
      uses: microsoft/[email protected]

    - name: Setup VSTest Console
      uses: darenm/[email protected]


#try nc -v -N 127.0.0.1 3334
 #curl http://localhost:3333 -I
 #vstest.console.exe ./Pico/Medman/FluidTransferTests/bin/Release/net481/FluidTransferTests.dll
#Start CoreServer.exe in background

    - name: Start CoreServer.exe in the background
      shell: cmd
      run: |
         echo git | .\Debug\CoreServer.exe -c -s &
         vstest.console.exe .\Tests\FluidTransferTests.dll

You see it just keeps spinning shows "waiting for SSL client" and doesn't proceed further to execute the tests.

Edit

As per the suggestion, in my run step I tried the following but still won't help still gives the same output.

- name: Start CoreServer.exe in the background
      shell: cmd
      run: |
         start /b echo git | .\Debug\CoreServer.exe -c -s
         vstest.console.exe .\Tests\FluidTransferTests.dll

Also tried, and still the same.

- name: Start CoreServer.exe in the background
      shell: cmd
      run: |
         start /B echo git | .\Debug\CoreServer.exe -c -s &  start /B vstest.console.exe .\Tests\FluidTransferTests.dll

Edit

I have tried many ways one of them is,

start /B "echo git | CoreServer.exe -c -s"

When I try like above it says, (c) Microsoft Corporation. All rights reserved. But surely its not running the Server.

Also tried:

start /B "" echo git | CoreServer.exe -c -s

But doing so looks like its not starting the server in background.