feat: add EXPECT_NO_COREFILE_DEATH

[zhouronghua]

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If we use expect_death, we really know it will coredump or raise signal, EXPECT_NO_COREFILE_DEATH is a helper for user to use expect_death but do not genreate core file. EXPECT_NO_COREFILE_DEATH depends on ::testing::ExceptionTest, who will set rlimit to suppress core file generated.

printf in main is not good idea for all test.

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