G-API: clean up accuracy tests (#14945)
* Delete createOutputMatrices flag
Update the way compile args function is created
Fix instantiation suffix print function
* Update comment (NB)
* Make printable comparison functions
* Use defines instead of objects for compile args
* Remove custom printers, use operator<< overload
* Remove SAME_TYPE and use -1 instead
* Delete createOutputMatrices flag in new tests
* Fix GetParam() printed values
* Update Resize tests: use CompareF object
* Address code review feedback
* Add default cases for operator<< overloads
* change throw to GAPI_Assert