Bump github.com/docker/cli

Bumps [github.com/docker/cli](https://github.com/docker/cli) from 20.10.14+incompatible to 20.10.15+incompatible.
- [Release notes](https://github.com/docker/cli/releases)
- [Commits](docker/cli@v20.10.14...v20.10.15)

---
updated-dependencies:
- dependency-name: github.com/docker/cli
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

go.mod

@@ -6,7 +6,7 @@ replace sigs.k8s.io/cluster-api => sigs.k8s.io/cluster-api v1.1.3
 
 require (
 	github.com/cppforlife/go-cli-ui v0.0.0-20200716203538-1e47f820817f
-	github.com/docker/cli v20.10.14+incompatible
+	github.com/docker/cli v20.10.15+incompatible
 	github.com/docker/docker v20.10.14+incompatible
 	github.com/go-logr/logr v1.2.0
 	github.com/jackpal/gateway v1.0.7

go.sum

@@ -380,8 +380,8 @@ github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13/go.mod h1:SqUrOPUn
 github.com/dgryski/go-sip13 v0.0.0-20181026042036-e10d5fee7954/go.mod h1:vAd38F8PWV+bWy6jNmig1y/TA+kYO4g3RSRF0IAv0no=
 github.com/dnaeon/go-vcr v1.0.1/go.mod h1:aBB1+wY4s93YsC3HHjMBMrwTj2R9FHDzUr9KyGc8n1E=
 github.com/docker/cli v20.10.7+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
-github.com/docker/cli v20.10.14+incompatible h1:dSBKJOVesDgHo7rbxlYjYsXe7gPzrTT+/cKQgpDAazg=
-github.com/docker/cli v20.10.14+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
+github.com/docker/cli v20.10.15+incompatible h1:HGO75iIgpyuG1m0hw0Kp7hY5o7XELmY1rsT9gIptOSU=
+github.com/docker/cli v20.10.15+incompatible/go.mod h1:JLrzqnKDaYBop7H2jaqPtU4hHvMKP+vjCwu2uszcLI8=
 github.com/docker/distribution v0.0.0-20190905152932-14b96e55d84c/go.mod h1:0+TTO4EOBfRPhZXAeF1Vu+W3hHZ8eLp8PgKVZlcvtFY=
 github.com/docker/distribution v2.7.1-0.20190205005809-0d3efadf0154+incompatible/go.mod h1:J2gT2udsDAN96Uj4KfcMRqY0/ypR+oyYUYmja8H+y+w=
 github.com/docker/distribution v2.7.1+incompatible h1:a5mlkVzth6W5A4fOsS3D2EO5BUmsJpcB+cRlLU7cSug=