Unittest crash (Core-6), on code in https://github.com/realm/realm-core/pull/3474

~~~
#0 0x00007ffff6710428 in __GI_raise (sig=sig@entry=6) at ../sysdeps/unix/sysv/linux/raise.c:54
#1 0x00007ffff671202a in __GI_abort () at abort.c:89
#2 0x0000000001d5b3a9 in please_report_this_error_to_help_at_realm_dot_io () at ../src/realm/util/terminate.cpp:53
#3 0x0000000001d5b6b2 in realm::util::terminate_internal (ss=...) at ../src/realm/util/terminate.cpp:123
#4 0x0000000001d5b7ec in realm::util::terminate(char const_, char const_, long, std::initializer_list<realm::util::Printable>&&) (
message=0x1d67252 "Assertion failed: ndx < m_size", file=0x1d6721e "../src/realm/array.hpp", line=1096,
values=<unknown type in /home/finn/sync/realm-core-6/build.debug/test/realm-tests, CU 0x1c60925, DIE 0x1c6164f>) at ../src/realm/util/terminate.cpp:140
#5 0x0000000000b5662c in realm::Array::get (this=0x7ffff000df78, ndx=1) at ../src/realm/array.hpp:1096
#6 0x0000000000b56541 in realm::Array::get_as_ref (this=0x7ffff000df78, ndx=1) at ../src/realm/array.hpp:1130
#7 0x0000000001cced24 in realm::Table::refresh_index_accessors (this=0x7ffff000db20) at ../src/realm/table.cpp:2291
#8 0x0000000001cd81e7 in realm::Table::refresh_accessor_tree (this=0x7ffff000db20) at ../src/realm/table.cpp:2268
#9 0x0000000001a49f0c in realm::Group::refresh_dirty_accessors (this=0x7fff34000dd0) at ../src/realm/group.cpp:1543
#10 0x0000000001a4a0ae in realm::Group::advance_transact (this=0x7fff34000dd0, new_top_ref=1664, new_file_size=4096, in=..., writable=false) at ../src/realm/group.cpp:1629
#11 0x0000000000d63312 in realm::Transaction::internal_advance_read<realm::_impl::NullInstructionObserver> (this=0x7fff34000dd0, observer=0x7ffeea7eb7d0, version_id=...,
hist=..., writable=false) at ../src/realm/db.hpp:968
#12 0x0000000000d62f61 in realm::Transaction::advance_read<realm::_impl::NullInstructionObserver> (this=0x7fff34000dd0, observer=0x7ffeea7eb7d0, version_id=...)
at ../src/realm/db.hpp:821
#13 0x0000000000d5aeec in realm::Transaction::advance_read (this=0x7fff34000dd0, target_version=...) at ../src/realm/db.hpp:555
#14 0x0000000000d579cb in (anonymous namespace)::handover_querier (control=0x7fffa7ffe6b0, test_context=..., db=warning: RTTI symbol not found for class 'std::Sp_counted_ptr_inplace<(anonymous namespace)::DBInit, std::allocator<(anonymous namespace)::DBInit>, (_gnu_cxx::_Lock_policy)2>'
warning: RTTI symbol not found for class 'std::Sp_counted_ptr_inplace<(anonymous namespace)::DBInit, std::allocator<(anonymous namespace)::DBInit>, (_gnu_cxx::_Lock_policy)2>'
std::shared_ptr (count 5, weak 1) 0x7fffa0000bc0)
at ../test/test_lang_bind_helper.cpp:3693
#15 0x0000000000d576d7 in Realm_UnitTest__LangBindHelper_HandoverBetweenThreads::test_run()::$_17::operator()() const (this=0x7fffa0001420)
at ../test/test_lang_bind_helper.cpp:3811
#16 0x0000000000d573e8 in realm::util::Thread::entry_point<Realm_UnitTest__LangBindHelper_HandoverBetweenThreads::test_run()::$_17>(void*) (cookie=0x7fffa0001420)
at ../src/realm/util/thread.hpp:478
#17 0x00007ffff6aac6ba in start_thread (arg=0x7ffeea7ec700) at pthread_create.c:333
#18 0x00007ffff67e241d in clone () at ../sysdeps/unix/sysv/linux/x86_64/clone.S:109

~~~