v6.0.0 release of PowerShell Core

Here are the major changes:

* Breaking changes

- Remove `sc` alias which conflicts with `sc.exe` (#5827)
- Separate group policy settings and enable policy controlled logging in PowerShell Core (#5791)

* Engine updates and fixes

- Handle `DLLImport` failure of `libpsrpclient` in PowerShell Remoting on Unix platforms (#5622)

* Test

- Replace `lee.io` Tests with `WebListener` (#5709) (Thanks @markekraus!)
- Update the docker based release package tests due to the removal of `Pester` module and other issues (#5692)
- Replace Remaining `HttpBin.org` Tests with `WebListener` (#5665) (Thanks @markekraus!)

* Build and Packaging Improvements

- Update x86 and x64 `MSI` packages to not overwrite each other (#5812) (Thanks @bergmeister!)
- Update `Restore-PSPester` to include the fix for nested describe errors (#5771)
- Automate the generation of release change log draft (#5712)

* Documentation and Help Content

- Updated help Uri to point to latest help content for `Microsoft.PowerShell.Core` module (#5820)
- Update the installation doc for `Raspberry-Pi` about supported devices (#5773)
- Fix a typo and a Markdown linting error in the Pull Request Template (#5807) (Thanks @markekraus!)
- Update submodule documentation for pester removal (#5786) (Thanks @bergmeister!)
- Change `Github` to `GitHub` in `CONTRIBUTING.md` (#5697) (Thanks @stuntguy3000!)
- Fix incorrect release date on the changelog (#5698) (Thanks @SwarfegaGit!)
- Add instructions to deploy `win-arm` build on Windows IoT (#5682)