Update bash

Changes:

- https://github.com/tianon/docker-bash/commit/c5cb170: Update to commit e4d38c2d74745ac1887aaaaba9f815f4f0d7822e
- https://github.com/tianon/docker-bash/commit/8bcaaf0: Update to commit 4d2700970a70cef98b157977ce40c4e0389cea44

library/bash

@@ -3,9 +3,9 @@
 Maintainers: Tianon Gravi <[email protected]> (@tianon)
 GitRepo: https://github.com/tianon/docker-bash.git
 
-Tags: devel-20200812, devel
+Tags: devel-20200819, devel
 Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
-GitCommit: d3bd18d5a38cb34c4fee3f079f4904cca2127ef2
+GitCommit: c5cb17095418bb2973cb7db879dab9fb92368828
 Directory: devel
 
 Tags: 5.1-alpha, 5.1-rc, rc