glibc: update to lastest 2.31 release HEAD
Includes the following fixes:
4f0a61f753 wordexp: handle overflow in positional parameter number (bug 28011)
8e88c0d888 Fix SXID_ERASE behavior in setuid programs (BZ #27471)
74a4425fae Enhance setuid-tunables test
bb5bb87959 tst-env-setuid: Use support_capture_subprogram_self_sgid
700264179c support: Add capability to fork an sgid child
7fa6d30eea support: Typo and formatting fixes
0de2b69c31 support: Pass environ to child process
0c92f409a7 S390: Also check vector support in memmove ifunc-selector [BZ #27511]
Signed-off-by: Steve Sakoman <steve@sakoman.com>
