test_users fails on SLES 15 when run with ASAN

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==3450==ERROR: AddressSanitizer: stack-buffer-overflow on address 0x7ffd5ccab3d0 at pc 0x7f01f27b1a96 bp 0x7ffd5cca3360 sp 0x7ffd5cca2b10

WRITE of size 131232 at 0x7ffd5ccab3d0 thread T0

    #0 0x7f01f27b1a95  (/usr/lib64/libasan.so.6+0x53a95)

    #1 0x7f01f219f5bc in maxscale::crypt(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /home/timofey_turenko_mariadb_com/MaxScale/server/core/utils.cc:729

    #2 0x7f01f2194294 in maxscale::Users::hash(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /home/timofey_turenko_mariadb_com/MaxScale/server/core/users.cc:270

    #3 0x7f01f21918a4 in maxscale::Users::add(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, maxscale::user_account_type) /home/timofey_turenko_mariadb_com/MaxScale/server/core/users.cc:75

    #4 0x7f01f1da0697 in admin_add_user /home/timofey_turenko_mariadb_com/MaxScale/server/core/adminusers.cc:136

    #5 0x7f01f1da230b in admin_add_inet_user(char const*, char const*, maxscale::user_account_type) /home/timofey_turenko_mariadb_com/MaxScale/server/core/adminusers.cc:372

    #6 0x7f01f1d9fab9 in rest_users_init() /home/timofey_turenko_mariadb_com/MaxScale/server/core/adminusers.cc:75

    #7 0x401392 in main /home/timofey_turenko_mariadb_com/MaxScale/server/core/test/test_adminusers.cc:83

    #8 0x7f01ef32129c in __libc_start_main (/lib64/libc.so.6+0x3529c)

    #9 0x401059 in _start (/home/timofey_turenko_mariadb_com/MaxScale/_build/server/core/test/test_adminusers+0x401059)

Address 0x7ffd5ccab3d0 is located in stack of thread T0 at offset 32832 in frame

    #0 0x7f01f219f449 in maxscale::crypt(std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&, std::__cxx11::basic_string<char, std::char_traits<char>, std::allocator<char> > const&) /home/timofey_turenko_mariadb_com/MaxScale/server/core/utils.cc:725

  This frame has 2 object(s):

    [48, 49) '<unknown>'

    [64, 32832) 'cdata' (line 727) <== Memory access at offset 32832 overflows this variable

HINT: this may be a false positive if your program uses some custom stack unwind mechanism, swapcontext or vfork

      (longjmp and C++ exceptions *are* supported)

SUMMARY: AddressSanitizer: stack-buffer-overflow (/usr/lib64/libasan.so.6+0x53a95) 

Shadow bytes around the buggy address:

  0x10002b98d620: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x10002b98d630: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x10002b98d640: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x10002b98d650: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

  0x10002b98d660: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00

=>0x10002b98d670: 00 00 00 00 00 00 00 00 00 00[f3]f3 f3 f3 f3 f3

  0x10002b98d680: f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 f3

  0x10002b98d690: f3 f3 f3 f3 f3 f3 f3 f3 f3 f3 00 00 00 00 00 00

  0x10002b98d6a0: 00 00 00 00 00 00 00 00 00 00 00 00 00 00 f1 f1

  0x10002b98d6b0: f1 f1 f1 f1 01 f2 00 f2 f2 f2 f8 f2 f2 f2 00 00

  0x10002b98d6c0: 00 f2 f2 f2 f2 f2 00 00 00 00 f2 f2 f2 f2 00 00

Shadow byte legend (one shadow byte represents 8 application bytes):

  Addressable:           00

  Partially addressable: 01 02 03 04 05 06 07 

  Heap left redzone:       fa

  Freed heap region:       fd

  Stack left redzone:      f1

  Stack mid redzone:       f2

  Stack right redzone:     f3

  Stack after return:      f5

  Stack use after scope:   f8

  Global redzone:          f9

  Global init order:       f6

  Poisoned by user:        f7

  Container overflow:      fc

  Array cookie:            ac

  Intra object redzone:    bb

  ASan internal:           fe

  Left alloca redzone:     ca

  Right alloca redzone:    cb

  Shadow gap:              cc

==3450==ABORTING