[tsan] Relax atexit5.cpp a bit more so it's not as dependent on the standard library implementation

GitOrigin-RevId: 0e099a64be7071f5109befaeb8e8534392192888
diff --git a/test/tsan/atexit5.cpp b/test/tsan/atexit5.cpp
index a784bc6..ef3b385 100644
--- a/test/tsan/atexit5.cpp
+++ b/test/tsan/atexit5.cpp
@@ -23,5 +23,5 @@
 // CHECK:   Write of size 8
 // The exact spelling and number of std frames is hard to guess.
 // CHECK:     unique_ptr
-// CHECK:     #{{1|2}} cxa_at_exit_callback_installed_at
-// CHECK:     #{{2|3}} __cxx_global_var_init
+// CHECK:     #{{[1-9]}} cxa_at_exit_callback_installed_at
+// CHECK:     #{{[2-9]}} __cxx_global_var_init