vendor: roll docker/distribution back to latest (v2.7.1) release

Now that 901bcb2231 was merged in containerd,
we no longer depend on the ParseDockerRef utility from docker/distribution,
so we can safely roll back to the latest release for this dependency.

Signed-off-by: Sebastiaan van Stijn <github@gone.nl>

vendor.conf

@@ -58,7 +58,7 @@ github.com/cilium/ebpf                              4032b1d8aae306b7bb94a2a11002
 # cri dependencies
 github.com/containerd/cri                           65830369b6b2b4edc454bf5cebbd9b76c1c1ac66 # master
 github.com/davecgh/go-spew                          v1.1.1
-github.com/docker/distribution                      0d3efadf0154c2b8a4e7b6621fff9809655cc580
+github.com/docker/distribution                      v2.7.1
 github.com/docker/docker                            4634ce647cf2ce2c6031129ccd109e557244986f
 github.com/docker/spdystream                        449fdfce4d962303d702fec724ef0ad181c92528
 github.com/emicklei/go-restful                      v2.9.5

vendor/github.com/docker/distribution/vendor.conf

@@ -7,7 +7,7 @@ github.com/beorn7/perks 4c0e84591b9aa9e6dcfdf3e020114cd81f89d5f9
 github.com/bugsnag/bugsnag-go b1d153021fcd90ca3f080db36bec96dc690fb274
 github.com/bugsnag/osext 0dd3f918b21bec95ace9dc86c7e70266cfc5c702
 github.com/bugsnag/panicwrap e2c28503fcd0675329da73bf48b33404db873782
-github.com/denverdino/aliyungo 6df11717a253d9c7d4141f9af4deaa7c580cd531
+github.com/denverdino/aliyungo afedced274aa9a7fcdd47ac97018f0f8db4e5de2
 github.com/dgrijalva/jwt-go a601269ab70c205d26370c16f7c81e9017c14e04
 github.com/docker/go-metrics 399ea8c73916000c64c2c76e8da00ca82f8387ab
 github.com/docker/libtrust fa567046d9b14f6aa788882a950d69651d230b21