MailboxProcessor docs using do! loop instead of return! loop

[chadunit]

Some of the snippets in the MailboxProcessor section (https://github.com/MicrosoftDocs/visualfsharpdocs/tree/live/docs/conceptual/snippets/fsmailboxprocessor) are using do! loop for their recursive calls.

It is my understanding that this is poor practice and return! should be used in these cases in order to avoid stack memory leaks.

I didn't check them all but a couple of instances are:

This snippet: https://github.com/MicrosoftDocs/visualfsharpdocs/blob/live/docs/conceptual/snippets/fsmailboxprocessor/snippet3.fs
used on page: https://github.com/MicrosoftDocs/visualfsharpdocs/blob/live/docs/conceptual/control.mailboxprocessor['msg]-class-[fsharp].md

And: https://github.com/MicrosoftDocs/visualfsharpdocs/blob/live/docs/conceptual/snippets/fsmailboxprocessor/snippet10.fs
used on: https://github.com/MicrosoftDocs/visualfsharpdocs/blob/live/docs/conceptual/mailboxprocessor.receive['msg]-method-[fsharp].md