refactor: replace sort.Slice with slices.Sort for natural ordering

[yingshanghuangqiao]

There is a new function added in the go1.21 standard library, which can make the code more concise and easy to read.

[jrick]

There is one more sort.Slice in this file that can be replaced.

dcrwallet/internal/rpc/jsonrpc/methods.go

Lines 2515 to 2517 in 4936efa

	sort.Slice(infos, func(i, j int) bool {
	return infos[i].ID < infos[j].ID
	})

can be rewritten as

	slices.SortFunc(infos, func(a, b *types.GetPeerInfoResult) int {
		switch {
		case a.ID < b.ID:
			return -1
		case a.ID > b.ID:
			return 1
		default:
			return 0
		}
	})

[yingshanghuangqiao]

There is one more sort.Slice in this file that can be replaced.

dcrwallet/internal/rpc/jsonrpc/methods.go

Lines 2515 to 2517 in 4936efa

	sort.Slice(infos, func(i, j int) bool {
	return infos[i].ID < infos[j].ID
	})

can be rewritten as

	slices.SortFunc(infos, func(a, b *types.GetPeerInfoResult) int {
		switch {
		case a.ID < b.ID:
			return -1
		case a.ID > b.ID:
			return 1
		default:
			return 0
		}
	})

Thank you for your guidance. I have made the suggested changes. Please review it again.