[Bug] Set-AzWcfRelay implemented pipeline in a wrong way

### Type of issue

Outdated article

### Feedback

(This is about the engineering docs.)

The piping best practices docs say this:

> For all resources, `-InputObject` should be implemented for at least the `Remove-*`, `Set-*` and `Update-*` cmdlets

This doesn't seem to be true for `Set-*` today, though:
- AutoRest doesn't automatically provide an -InputObject implementation, as far as we can tell
- Manually implementing it is hard. In a help channel, @VeryEarly mentioned that "To have similar functionality requires similar customization and as you can see it is quite complicated."
- Several major Azure resources don't support it for Set-, e.g. `Set-AzStorageAccount`, `Set-AzVM`

Suspect the docs are outdated here, or at least don't apply for AutoRest-based cmdlets.

### Page URL

https://github.com/Azure/azure-powershell/blob/b08bc7cb8c20c5302d126dda1ce89967d124b9ce/documentation/development-docs/design-guidelines/piping-best-practices.md

### Content source URL

https://github.com/Azure/azure-powershell/blob/b08bc7cb8c20c5302d126dda1ce89967d124b9ce/documentation/development-docs/design-guidelines/piping-best-practices.md?plain=1#L32

### Author

_No response_

### Document Id

_No response_

Open documentation/development-docs/design-guidelines/piping-best-practices.md at the linked guidance around line 32 and review the statement about -InputObject for Set-* cmdlets. Compare it with the reported AutoRest behavior and the named Set-AzStorageAccount and Set-AzVM examples. Done means the engineering documentation accurately describes the applicable piping guidance.

Written by the indexing model from the issue text.