Log Message:
Update shells/bash from 5.2.12 to 5.2.15 by adding the 3 most
recent releases patches, which fix:

Patch-13:
	Bash can leak memory when referencing a noneexistent
	associative array element.

Patch-14:
	Bash defers processing additional terminating signals when
	running the EXIT trap while exiting due to a terminating signal.
	This patch allows the new terminating signal to kill the shell
	immediately.

Patch-15:
	There are several cases where bash is too aggressive when
	optimizing out forks in subshells. For example, `eval' and
	traps should never be optimized.