Remove obsolete workflow methods

[famarting]

equivalent to dapr/dotnet-sdk#1344

the workflow methods defined here https://github.com/dapr/go-sdk/blob/main/client/workflow.go use a deprecated API and we aim to delete them

instead this client should be used https://github.com/dapr/go-sdk/blob/main/workflow/client.go and any docs should be updated to make use of it

[famarting]

this issue can be closed since this has been merged #640

this issue does not consist of literally removing the workflow methods, but instead deprecating them and stop advising users to use them

[mikeee]

IMO - idiomatic deprecation comments should be added to the relevant client methods before we bottom this issue out completely. e.g.

client/workflow.go

...
// StartWorkflowBeta1 starts a workflow using the beta1 spec.
// 
// Deprecated: Please use the workflow client (github.com/dapr/go-sdk/workflow).
// These methods of managing workflows are no longer supported and will be removed in the
// next release.
...

Wdyt @famarting?

[famarting]

agree agree, will send a PR now adding these comments everywhere

[mikeee]

Looks great, thanks for sorting this out 🚀