Update bash

Changes:

- https://github.com/tianon/docker-bash/commit/6cf7d99: Update to commit 2dc823ee9663f2a011677aa95bfb5d183360d81f

library/bash

@@ -3,9 +3,9 @@
 Maintainers: Tianon Gravi <[email protected]> (@tianon)
 GitRepo: https://github.com/tianon/docker-bash.git
 
-Tags: devel-20190822, devel
+Tags: devel-20190823, devel
 Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
-GitCommit: ed2e30dbdebf6b86815a9ba5cae2b4e8bcab406f
+GitCommit: 6cf7d9949ac6597241ac765021a7c590610d598c
 Directory: devel
 
 Tags: 5.0.9, 5.0, 5, latest