fix: zero attempts

[helsonxiao]

Checklist

• [x] npm test passes
• [ ] tests and/or benchmarks are included
• [ ] documentation is changed or added
• [x] commit message follows commit guidelines

Affected core subsystem(s)

• listener
• job

Description of change

static get attempts() {
  return 0;
}

Before: If job / listener return 0 in attempts, then it'll use global attempts which is 5 as a fallback. After: If job / listener return 0 in attempts, no retry anymore.

[seekcx]

Good job!

[helsonxiao]

Good night!