IVGCVSW-6176 Add support for shape_signature in the tflite parser

* tflite shape_signatures will now be the preferred way to detect dynamic tensors
* add test utility to the parser that converts a model's tensors to dynamic
* by default tests will run a dynamic version of the model in addition to the original
* fix dynamic shape inference of unpack operator
* reactivate and fix quantize test
* add shape inference to expand dims

Signed-off-by: Finn Williams <Finn.Williams@arm.com>
Change-Id: If11ba19d813cd3590707583dff1e4eb0e6412a1d