Add "debug" button for test steps in vscode

[nicolo-ribaudo]

Deno.test is prefixed with two actions: "Run" and "Debug", to run (with or without debugger) the specific test.

t.step only supports running the individual step without the debugger, by clicking on the "play" button on the line number of the t.step line. It would be great have a way to easily debug a single step.

[justinmchase]

Or is there a way to specify that only a particular step should be run, such as by adding { only: true } for a step? And then debugging at the test level would only debug the one step.