feat: Improve verbose logging - print failed task

[Drino]

Add a message to verbose log to simplify understanding which task caused overall failure.

Before:

$ cat Taskfile.yml
version: '3'

tasks:
  default:
    deps: [hello, fails]
    
  hello:
    cmds: [echo "Hello"]
     
  fails:
    cmds: ['sleep 2 && exit 42']
$ ./task -v
task: "default" started
task: "fails" started
task: [fails] sleep 2 && exit 42
task: "hello" started
task: [hello] echo "Hello"
Hello
task: "hello" finished
exit status 42

After:

$ ./task -v
task: "default" started
task: "fails" started
task: [fails] sleep 2 && exit 42
task: "hello" started
task: [hello] echo "Hello"
Hello
task: "hello" finished
task: "fails" failed: exit status 42
exit status 42