[Feature]: Set-AzSynapse* and Set-AzDataFactoryV2* should accept objects

### Description of the new feature

I'm unsure if it was intentional, but I think it would be ideal if one can construct `[PSSubResource]`s in memory to deploy to workspaces/studio, similar to `New-AzDeployment`'s `TemplateObject`/`TemplateParameterObject`.

### Proposed implementation details (optional)

```powershell
[Microsoft.Azure.Commands.Synapse.Models.PSPipelineResource]$pipeline =
@{
name = "Pipeline 1"
properties = @{
annotations = @()
}
}

Set-AzSynapsePipeline -DefinitionObject $pipeline

```

It's helpful for things like Poor Man's Dataset Parameterization, but can also be useful for particular tests.