defaultvalueprovider_ut fails on address sanitizer

[mint570]

Enable address sanitizer in unit test.
Test output:

[----------] 4 tests from DECORATOR
[ RUN ] DECORATOR.ChoiceAndLeaflistDefaultValue
AddressSanitizer:DEADLYSIGNAL

==13684==ERROR: AddressSanitizer: SEGV on unknown address 0x000000003232 (pc 0x7f6f2bbdead8 bp 0x7ffc8ec81c60 sp 0x7ffc8ec81408 T0)
==13684==The signal is caused by a READ memory access.
#0 0x7f6f2bbdead8 (/lib/x86_64-linux-gnu/libc.so.6+0x172ad8)
#1 0x562b574e620c in __interceptor_strlen.part.0 (/tmp/sonic/tests/.libs/tests_asan+0x52a20c)
#2 0x7f6f2bedd057 in std::__cxx11::basic_string<char, std::char_traits, std::allocator >::basic_string(char const*, std::allocator const&) (/usr/lib/x86_64-linux-gnu/libstdc++.so.6+0x136057)
#3 0x562b5795f135 in swss::JSon::buildJson[abi:cxx11](char const**) ../common/json.cpp:34
#4 0x562b57942c8b in swss::DefaultValueHelper::GetDefaultValueInfoForLeaflist(lys_node_leaflist*, std::shared_ptr<std::map<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::less<std::__cxx11::basic_string<char, std::char_traits, std::allocator > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator > const, std::__cxx11::basic_string<char, std::char_traits, std::allocator > > > > >) ../common/defaultvalueprovider.cpp:228
#5 0x562b579432a7 in swss::DefaultValueHelper::GetDefaultValueInfoabi:cxx11 ../common/defaultvalueprovider.cpp:264
#6 0x562b57943501 in swss::DefaultValueHelper::BuildTableDefaultValueMapping(lys_node*, std::map<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, int>, std::shared_ptr<std::map<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::less<std::__cxx11::basic_string<char, std::char_traits, std::allocator > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator > const, std::__cxx11::basic_string<char, std::char_traits, std::allocator > > > > >, std::less<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, int> >, std::allocator<std::pair<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, int> const, std::shared_ptr<std::map<std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::__cxx11::basic_string<char, std::char_traits, std::allocator >, std::less<std::__cxx11::basic_string<char, std::char_traits, std::allocator > >, std::allocator<std::pair<std::__cxx11::basic_string<char, std::char_traits, std::allocator > const, std::__cxx11::basic_string<char, std::char_traits, std::allocator > > > > > > > >&) ../common/defaultvalueprovider.cpp:293
#7 0x562b57943736 in swss::DefaultValueProvider::AppendTableInfoToMapping(lys_node*) ../common/defaultvalueprovider.cpp:306
#8 0x562b579454f1 in swss::DefaultValueProvider::LoadModule(std::__cxx11::basic_string<char, std::char_traits, std::allocator > const&, std::__cxx11::basic_string<char, std::char_traits, std::allocator > const&, ly_ctx*) ../common/defaultvalueprovider.cpp:487
#9 0x562b57944f46 in swss::DefaultValueProvider::Initialize(char const*) ../common/defaultvalueprovider.cpp:445
#10 0x562b577b5e0a in MockDefaultValueProvider::MockInitialize(char const*) /tmp/sonic/tests/defaultvalueprovider_ut.cpp:15
#11 0x562b577af783 in DECORATOR_ChoiceAndLeaflistDefaultValue_Test::TestBody() /tmp/sonic/tests/defaultvalueprovider_ut.cpp:22
#12 0x562b57a24ad6 in void testing::internal::HandleExceptionsInMethodIfSupported<testing::Test, void>(testing::Test*, void (testing::Test::)(), char const) (/tmp/sonic/tests/.libs/tests_asan+0xa68ad6)
#13 0x562b57a1ab4d in testing::Test::Run() (/tmp/sonic/tests/.libs/tests_asan+0xa5eb4d)
#14 0x562b57a1aca4 in testing::TestInfo::Run() (/tmp/sonic/tests/.libs/tests_asan+0xa5eca4)
#15 0x562b57a1b138 in testing::TestSuite::Run() (/tmp/sonic/tests/.libs/tests_asan+0xa5f138)
#16 0x562b57a1b781 in testing::internal::UnitTestImpl::RunAllTests() (/tmp/sonic/tests/.libs/tests_asan+0xa5f781)
#17 0x562b57a25046 in bool testing::internal::HandleExceptionsInMethodIfSupported<testing::internal::UnitTestImpl, bool>(testing::internal::UnitTestImpl*, bool (testing::internal::UnitTestImpl::)(), char const) (/tmp/sonic/tests/.libs/tests_asan+0xa69046)
#18 0x562b57a1ad67 in testing::UnitTest::Run() (/tmp/sonic/tests/.libs/tests_asan+0xa5ed67)
#19 0x562b578b4e4f in RUN_ALL_TESTS() /usr/include/gtest/gtest.h:2486
#20 0x562b578b4921 in main /tmp/sonic/tests/main.cpp:83
#21 0x7f6f2ba8fd09 in __libc_start_main ../csu/libc-start.c:308
#22 0x562b574cd319 in _start (/tmp/sonic/tests/.libs/tests_asan+0x511319)

AddressSanitizer can not provide additional info.
SUMMARY: AddressSanitizer: SEGV (/lib/x86_64-linux-gnu/libc.so.6+0x172ad8)
==13684==ABORTING

[mint570]

@liuh-80