rebase: bump github.com/prometheus/client_golang from 1.11.0 to 1.12.0

Bumps [github.com/prometheus/client_golang](https://github.com/prometheus/client_golang) from 1.11.0 to 1.12.0.
- [Release notes](https://github.com/prometheus/client_golang/releases)
- [Changelog](https://github.com/prometheus/client_golang/blob/main/CHANGELOG.md)
- [Commits](https://github.com/prometheus/client_golang/compare/v1.11.0...v1.12.0)

---
updated-dependencies:
- dependency-name: github.com/prometheus/client_golang
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/prometheus/procfs/netstat.go

@@ -0,0 +1,68 @@
+// Copyright 2020 The Prometheus Authors
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+// http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+package procfs
+
+import (
+	"bufio"
+	"os"
+	"path/filepath"
+	"strconv"
+	"strings"
+)
+
+// NetStat contains statistics for all the counters from one file
+type NetStat struct {
+	Filename string
+	Stats    map[string][]uint64
+}
+
+// NetStat retrieves stats from /proc/net/stat/
+func (fs FS) NetStat() ([]NetStat, error) {
+	statFiles, err := filepath.Glob(fs.proc.Path("net/stat/*"))
+	if err != nil {
+		return nil, err
+	}
+
+	var netStatsTotal []NetStat
+
+	for _, filePath := range statFiles {
+		file, err := os.Open(filePath)
+		if err != nil {
+			return nil, err
+		}
+
+		netStatFile := NetStat{
+			Filename: filepath.Base(filePath),
+			Stats:    make(map[string][]uint64),
+		}
+		scanner := bufio.NewScanner(file)
+		scanner.Scan()
+		// First string is always a header for stats
+		var headers []string
+		headers = append(headers, strings.Fields(scanner.Text())...)
+
+		// Other strings represent per-CPU counters
+		for scanner.Scan() {
+			for num, counter := range strings.Fields(scanner.Text()) {
+				value, err := strconv.ParseUint(counter, 16, 32)
+				if err != nil {
+					return nil, err
+				}
+				netStatFile.Stats[headers[num]] = append(netStatFile.Stats[headers[num]], value)
+			}
+		}
+		netStatsTotal = append(netStatsTotal, netStatFile)
+	}
+	return netStatsTotal, nil
+}