Update bash

Changes:

- https://github.com/tianon/docker-bash/commit/6cdcb0a: Update to commit 87d2ae2ae5d690df6f1c05a463edf11ea218159e

library/bash

@@ -3,9 +3,9 @@
 Maintainers: Tianon Gravi <[email protected]> (@tianon)
 GitRepo: https://github.com/tianon/docker-bash.git
 
-Tags: devel-20200417, devel
+Tags: devel-20200420, devel
 Architectures: amd64, arm32v6, arm32v7, arm64v8, i386, ppc64le, s390x
-GitCommit: 507d7d41cadc0cb879dcb319c11c163cfb8df1f8
+GitCommit: 6cdcb0aa849830fbd64d6784c5dde58d1d79f20a
 Directory: devel
 
 Tags: 5.0.16, 5.0, 5, latest