too big tolerance for SerializeTest.HostCKKSCiphertext

[black6816]

hi, i find the test case SerializeTest.HostCKKSCiphertext ailed some times， so，i change the test code to

    TEST(SerializeTest, HostCKKSCiphertext) {
        for(int i=0;i<100;i++) {
            printf("i=%2d\n", i);
        GeneralHeContext ghe(false, SchemeType::CKKS, 32, 0, { 60, 60, 60 }, false, 0x123, 10, 1<<16, 1e-2);
        test_ciphertext(ghe);
        }
    }

then , this test will fail.
if i change tolerance to 1e-1 or 1.8e-2，the test case can pass.

[lightbulb128]

I think that is the expected behavior. For higher precision you might want to set the scale larger.