Prevent generating test case when align_corners and half_pixel are both true in nearest mode

Note:
- align_corners and half_pixel can both be true in nearest mode for tfl
but not tf
- this is inconsistent between tf and tfl

Signed-off-by: Jerry Ge <jerry.ge@arm.com>
Change-Id: Ib396f994874904e017e0d696f70370bd51d60161