You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: job_cleaner.go
    path of file: ./repos/river/internal/maintenance
    
    the code of the file until where you have to start completion: package maintenance

import (
	"context"
	"errors"
	"fmt"
	"log/slog"
	"time"

	"github.com/riverqueue/river/internal/baseservice"
	"github.com/riverqueue/river/internal/maintenance/startstop"
	"github.com/riverqueue/river/internal/rivercommon"
	"github.com/riverqueue/river/internal/util/timeutil"
	"github.com/riverqueue/river/internal/util/valutil"
	"github.com/riverqueue/river/riverdriver"
)

const (
	CancelledJob
    
func (c *JobCleanerConfig) mustValidate() *JobCleanerConfig {
	if c.CancelledJobRetentionPeriod <= 0 {
		panic("JobCleanerConfig.CancelledJobRetentionPeriod must be above zero")
	}
	if c.CompletedJobRetentionPeriod <= 0 {
		panic("JobCleanerConfig.CompletedJobRetentionPeriod must be above zero")
	}
	if c.DiscardedJobRetentionPeriod <= 0 {
		panic("JobCleanerConfig.DiscardedJobRetentionPeriod must be above zero")
	}
	if c.Interval <= 0 {
		panic("JobCleanerConfig.Interval must be above zero")
	}

	return c
}