catch-22 regarding running `dotnet restore` vs. `dotnet workload restore` first

### Describe the bug

My CI build is broken on some agents because there seems to be a catch-22 regarding whether to run `dotnet restore` or `dotnet workload restore` first.

If I run `dotnet restore` first, it errors out saying "error NETSDK1147: To install these workloads, run the following command: dotnet workload restore".

If I run `dotnet workload restore` first, it errors out saying "The SDK 'Microsoft.Build.Traversal' specified could not be found."

Yes, I have traversal projects. And in fact the root of my restore operation is a `dirs.proj`.

### To Reproduce

I suspect all you need is a dirs.proj that points to a project that requires android, iOS or anything else requiring a workload.
Then, on a computer that does not already have a nuget cache with `Microsoft.Build.Traversal` or the required workload installed, try restoring.

### Further technical details

SDK Version: 9.0.100

This happens on mac, windows and linux agents. These are custom agents, BTW, so they don't have a bunch of workloads pre-installed as the Azure Pipelines Hosted agents may have.