fix: Avoid trimming characters incorrectly from ProcStatus

[irvinlim]

Hello, thank you for the wonderful library!

We found some issues in parsing ProcStatus, in particular those whose Name starts with a k. For a simple repro (I copied out the existing code from https://github.com/prometheus/procfs/blob/bf361025088d9df7a76662269f07facf20f8711e/proc_status.go):

package main

import (
	"bytes"
	"fmt"
	"strconv"
	"strings"

	"github.com/prometheus/procfs"
)

const (
	pid  = 6187
	data = `Name:   kube-proxy`
)

func main() {
	s := procfs.ProcStatus{PID: pid}

	lines := strings.Split(data, "\n")
	for _, line := range lines {
		if !bytes.Contains([]byte(line), []byte(":")) {
			continue
		}

		kv := strings.SplitN(line, ":", 2)

		// removes spaces
		k := string(strings.TrimSpace(kv[0]))
		v := string(strings.TrimSpace(kv[1]))
		// removes "kB"
		v = string(bytes.Trim([]byte(v), " kB"))

		// value to int when possible
		// we can skip error check here, 'cause vKBytes is not used when value is a string
		vKBytes, _ := strconv.ParseUint(v, 10, 64)
		// convert kB to B
		vBytes := vKBytes * 1024

		fillStatus(&s, k, v, vKBytes, vBytes)
	}

	fmt.Printf("%v\n", s.Name)
}

The output is as follows:

ube-proxy

The reason is because bytes.Trim takes in a cutSet, not a suffix that should be trimmed. As such, this PR modifies bytes.Trim to strings.TrimSuffix.

[discordianfish]

Good catch, thanks!

[SuperQ]

Thanks!