Update rabbitmq

Changes:

- https://github.com/docker-library/rabbitmq/commit/bb688c9: Merge pull request https://github.com/docker-library/rabbitmq/pull/384 from J0WI/alpine11
- https://github.com/docker-library/rabbitmq/commit/4a6c258: Upgrade Alpine to 3.11

library/rabbitmq

@@ -16,7 +16,7 @@ Directory: 3.8/ubuntu/management
 
 Tags: 3.8.2-alpine, 3.8-alpine, 3-alpine, alpine
 Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
-GitCommit: facda0977005887a4b42dd06f3f8eac8f6cf7169
+GitCommit: 4a6c2586ecdfffdca39abe5275b84a4823a295fb
 Directory: 3.8/alpine
 
 Tags: 3.8.2-management-alpine, 3.8-management-alpine, 3-management-alpine, management-alpine
@@ -36,7 +36,7 @@ Directory: 3.7/ubuntu/management
 
 Tags: 3.7.23-alpine, 3.7-alpine
 Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
-GitCommit: 02e414da9cec271874dcd17fda695897cdbe5ae4
+GitCommit: 4a6c2586ecdfffdca39abe5275b84a4823a295fb
 Directory: 3.7/alpine
 
 Tags: 3.7.23-management-alpine, 3.7-management-alpine