Restart request should have config argument to check if configuration changed

[isidorn]

Related VS Code issue microsoft/vscode#118196

Today the spec of the DAP restart request doesn't say anything about changed launch configurations.
But we could add an optional config argument to the restart request so that an implementation has easy access to it and can compare it with the current values.

[weinand]

The restart request now takes an argument for the "launch" or "attach" configuration.