sh: Increase default history size to POSIX mandated minimum of 128

The default history size in bin/sh is currently 100 however POSIX.1-2024
mandates that a default greater than or equal to 128 shall be used,
therefore this increases the default history size in /bin/sh to 128.

POSIX standards reference:
https://pubs.opengroup.org/onlinepubs/9799919799/utilities/sh.html#tag_20_110_08

MFC after: 3 days
Reviewed by: emaste, jilles, jlduran, ziaee
Signed-off-by: Kristofer Peterson <kris@tranception.com>
Closes: https://github.com/freebsd/freebsd-src/pull/2093

(cherry picked from commit 81b2055c49dec8884d7bb23503f1dfeac37ac95d)