build(deps): bump github.com/docker/distribution

Bumps [github.com/docker/distribution](https://github.com/docker/distribution) from 2.7.1+incompatible to 2.8.0+incompatible.
- [Release notes](https://github.com/docker/distribution/releases)
- [Commits](https://github.com/docker/distribution/compare/v2.7.1...v2.8.0)

---
updated-dependencies:
- dependency-name: github.com/docker/distribution
  dependency-type: direct:production
...

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

vendor/github.com/docker/distribution/registry/api/errcode/errors.go

@@ -207,11 +207,11 @@ func (errs Errors) MarshalJSON() ([]byte, error) {
 	for _, daErr := range errs {
 		var err Error
 
-		switch daErr.(type) {
+		switch daErr := daErr.(type) {
 		case ErrorCode:
-			err = daErr.(ErrorCode).WithDetail(nil)
+			err = daErr.WithDetail(nil)
 		case Error:
-			err = daErr.(Error)
+			err = daErr
 		default:
 			err = ErrorCodeUnknown.WithDetail(daErr)
 

vendor/github.com/docker/distribution/registry/api/v2/urls.go

@@ -252,15 +252,3 @@ func appendValuesURL(u *url.URL, values ...url.Values) *url.URL {
 	u.RawQuery = merged.Encode()
 	return u
 }
-
-// appendValues appends the parameters to the url. Panics if the string is not
-// a url.
-func appendValues(u string, values ...url.Values) string {
-	up, err := url.Parse(u)
-
-	if err != nil {
-		panic(err) // should never happen
-	}
-
-	return appendValuesURL(up, values...).String()
-}

vendor/github.com/docker/distribution/registry/client/auth/challenge/authchallenge.go

@@ -117,8 +117,8 @@ func init() {
 		var t octetType
 		isCtl := c <= 31 || c == 127
 		isChar := 0 <= c && c <= 127
-		isSeparator := strings.IndexRune(" \t\"(),/:;<=>?@[]\\{}", rune(c)) >= 0
-		if strings.IndexRune(" \t\r\n", rune(c)) >= 0 {
+		isSeparator := strings.ContainsRune(" \t\"(),/:;<=>?@[]\\{}", rune(c))
+		if strings.ContainsRune(" \t\r\n", rune(c)) {
 			t |= isSpace
 		}
 		if isChar && !isCtl && !isSeparator {

vendor/github.com/docker/distribution/registry/client/repository.go

@@ -16,7 +16,7 @@ import (
 
 	"github.com/docker/distribution"
 	"github.com/docker/distribution/reference"
-	"github.com/docker/distribution/registry/api/v2"
+	v2 "github.com/docker/distribution/registry/api/v2"
 	"github.com/docker/distribution/registry/client/transport"
 	"github.com/docker/distribution/registry/storage/cache"
 	"github.com/docker/distribution/registry/storage/cache/memory"
@@ -736,7 +736,12 @@ func (bs *blobs) Create(ctx context.Context, options ...distribution.BlobCreateO
 		return nil, err
 	}
 
-	resp, err := bs.client.Post(u, "", nil)
+	req, err := http.NewRequest("POST", u, nil)
+	if err != nil {
+		return nil, err
+	}
+
+	resp, err := bs.client.Do(req)
 	if err != nil {
 		return nil, err
 	}