Fix enc_photon_noise_test with older versions of GoogleTest
Fix enc_photon_noise_test with older versions of GoogleTest

This does not rely on the tuple-matching version of FloatNear anymore.

libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl,libjxl/libjxl