TEST: bash 5.2.15-2

[Corinna Vinschen]

The following packages have been uploaded to the Cygwin distribution:

* bash-5.2.15-2
* bash-devel-5.2.15-2

v2: Make /usr/bin/sh.exe a hardlink to /usr/bin/bash.exe, as required.
    The v1 installer script accidentally created a symlink.

This is a long overdue update of the bash shell.  Given the big step in
the version, this is a TEST release for now.  Please give it a try.

This release is based on the Fedora Linux 37 bash release with most
patches from Fedora used for the Cygwin release, too.  

This includes noticably:

- A bash-devel package

- Real executables for some builtins in /usr/bin.  This is actually  
  required per POSIX.  For a discussion, see
  https://bugzilla.redhat.com/show_bug.cgi?id=820192


Bash is an sh-compatible shell that incorporates useful features
from the Korn shell (ksh) and C shell (csh).  It is intended to conform to the
IEEE POSIX P1003.2/ISO 9945.2 Shell and Tools standard.  It offers functional
improvements over sh for both programming and interactive use. In addition,
most sh scripts can be run by Bash without modification.