Enable building compression/python/compression_test using bazel.
Add default image path for image_test and paligemma_test.
PiperOrigin-RevId: 720583438
See https://arxiv.org/abs/2407.07726 for a description of the model.
Because PaliGemma operates as a prefix-LM on the image+prompt, add support for that.
PiperOrigin-RevId: 677841119