Update Docker 17.12 to use Alpine 3.7

library/docker

@@ -6,7 +6,7 @@ GitRepo: https://github.com/docker-library/docker.git
 
 Tags: 17.12.0-ce, 17.12.0, 17.12, 17, stable, test, latest
 Architectures: amd64, arm64v8, ppc64le, s390x
-GitCommit: de9fda490429cf83734ef78b58f0ae9cfed1b087
+GitCommit: 51ba3bdf3e104e8af01150daec9122c4fbeaa41e
 Directory: 17.12
 
 Tags: 17.12.0-ce-dind, 17.12.0-dind, 17.12-dind, 17-dind, stable-dind, test-dind, dind