go: update most dependencies to the latest version

It's a lot of work for dependabot for our outdated deps, let's
help it by making one huge manual update.

Signed-off-by: Ondřej Budai <ondrej@budai.cz>

vendor/cloud.google.com/go/compute/metadata/metadata.go

@@ -32,6 +32,8 @@ import (
 	"strings"
 	"sync"
 	"time"
+
+	"github.com/googleapis/gax-go/v2"
 )
 
 const (
@@ -282,6 +284,7 @@ func NewClient(c *http.Client) *Client {
 // getETag returns a value from the metadata service as well as the associated ETag.
 // This func is otherwise equivalent to Get.
 func (c *Client) getETag(suffix string) (value, etag string, err error) {
+	ctx := context.TODO()
 	// Using a fixed IP makes it very difficult to spoof the metadata service in
 	// a container, which is an important use-case for local testing of cloud
 	// deployments. To enable spoofing of the metadata service, the environment
@@ -304,9 +307,25 @@ func (c *Client) getETag(suffix string) (value, etag string, err error) {
 	}
 	req.Header.Set("Metadata-Flavor", "Google")
 	req.Header.Set("User-Agent", userAgent)
-	res, err := c.hc.Do(req)
-	if err != nil {
-		return "", "", err
+	var res *http.Response
+	var reqErr error
+	retryer := newRetryer()
+	for {
+		res, reqErr = c.hc.Do(req)
+		var code int
+		if res != nil {
+			code = res.StatusCode
+		}
+		if delay, shouldRetry := retryer.Retry(code, reqErr); shouldRetry {
+			if err := gax.Sleep(ctx, delay); err != nil {
+				return "", "", err
+			}
+			continue
+		}
+		break
+	}
+	if reqErr != nil {
+		return "", "", nil
 	}
 	defer res.Body.Close()
 	if res.StatusCode == http.StatusNotFound {

vendor/cloud.google.com/go/compute/metadata/retry.go

@@ -0,0 +1,81 @@
+// Copyright 2021 Google LLC
+//
+// 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 metadata
+
+import (
+	"io"
+	"net/http"
+	"time"
+
+	"github.com/googleapis/gax-go/v2"
+)
+
+const (
+	maxRetryAttempts = 5
+)
+
+var (
+	syscallRetryable = func(err error) bool { return false }
+)
+
+func newRetryer() *metadataRetryer {
+	return &metadataRetryer{bo: &gax.Backoff{Initial: 100 * time.Millisecond}}
+}
+
+type backoff interface {
+	Pause() time.Duration
+}
+
+type metadataRetryer struct {
+	bo       backoff
+	attempts int
+}
+
+func (r *metadataRetryer) Retry(status int, err error) (time.Duration, bool) {
+	if status == http.StatusOK {
+		return 0, false
+	}
+	retryOk := shouldRetry(status, err)
+	if !retryOk {
+		return 0, false
+	}
+	if r.attempts == maxRetryAttempts {
+		return 0, false
+	}
+	r.attempts++
+	return r.bo.Pause(), true
+}
+
+func shouldRetry(status int, err error) bool {
+	if 500 <= status && status <= 599 {
+		return true
+	}
+	if err == io.ErrUnexpectedEOF {
+		return true
+	}
+	// Transient network errors should be retried.
+	if syscallRetryable(err) {
+		return true
+	}
+	if err, ok := err.(interface{ Temporary() bool }); ok {
+		if err.Temporary() {
+			return true
+		}
+	}
+	if err, ok := err.(interface{ Unwrap() error }); ok {
+		return shouldRetry(status, err.Unwrap())
+	}
+	return false
+}

vendor/cloud.google.com/go/compute/metadata/retry_linux.go

@@ -0,0 +1,26 @@
+// Copyright 2021 Google LLC
+//
+// 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.
+
+//go:build linux
+// +build linux
+
+package metadata
+
+import "syscall"
+
+func init() {
+	// Initialize syscallRetryable to return true on transient socket-level
+	// errors. These errors are specific to Linux.
+	syscallRetryable = func(err error) bool { return err == syscall.ECONNRESET || err == syscall.ECONNREFUSED }
+}