sample.callstack failing sometimes on x86-32 on ubuntu22 GA CI

[derekbruening]

https://github.com/DynamoRIO/dynamorio/actions/runs/14001557078/job/39208835327?pr=7391

249: wrapping /usr/lib32/libc.so.6!malloc
249: malloc called from:
249:   libc.so.6!<unknown>
249:   libc.so.6!<unknown>
249:   <unknown module> @0x8890ff00
249:   <unknown module> @0x00000004
249:   ld-linux.so.2!<unknown>
249:   <unknown module> @0x00010101
249: <Application /home/runner/work/dynamorio/dynamorio/build_debug-internal-32/suite/tests/bin/common.alloc (24410).  DynamoRIO Sample Client 'callstack' internal crash at PC 0xea728dde.  Please report this at http://dynamorio.org/issues.  Program aborted.
249: Received SIGSEGV at pc 0xea728dde in thread 24410
249: Base: 0xea7af000
249: Registers:eax=0x00000003 ebx=0xea734000 ecx=0x464c4000 edx=0x00000000
249: 	esi=0x464c4583 edi=0x447e13b4 esp=0x4468e980 ebp=0xea738164
249: 	efla
249: version 11.90.20168, custom build
249: -no_dynamic_options -client_lib '/home/runner/work/dynamorio/dynamorio/build_debug-internal-32/api/samples/../bin/libcallstack.so;0;' -client_lib32 '/home/runner/work/dynamorio/dynamorio/build_debug-internal-32/api/samples/../bin/libcallstack.so;0;' -code_api -stderr_mask 12 -stack_size 56K -signal_stack_size 32K -max_el
249: 0xea738164 0xe67a2000
249: 0xea7a7000 0x00000000>
241/379 Test #249: code_api|sample.callstack ........................................***Failed  Required regular expression not found. Regex=[^wrapping .*malloc
malloc called from:
.*
Hello world!
$
]  1.86 sec

[derekbruening]

Xref #7359

[derekbruening]

This keeps happening, this time in master merge: http://github.com/DynamoRIO/dynamorio/actions/runs/14130503857