service/dap: limit the number of goroutines to return from a threads request (#2595)
service/dap: limit the number of goroutines to return from a threads request (#2595)

This adds a cap and a log message if there are many goroutines. This will help
prevent the debugger from freezing, but does not yet address making sure the
interesting goroutines are the ones that are returned.

Updates golang/vscode-go#129
go-delve/delve,go-delve/delve,go-delve/delve,go-delve/delve,go-delve/delve