Fix CL Compiler frontend failure for ArgMinMax

Fix CL Compiler frontend failure for ArgMinMax

- Change select condition's data type to satisfy its signature
- Add failing test case with VEC_SIZE == 1

Resolve: COMPMID-4110

Change-Id: I52287bff7a2108f92fd12164e267df6c074d5508
Signed-off-by: Giorgio Arena <giorgio.arena@arm.com>
Reviewed-on: https://review.mlplatform.org/c/ml/ComputeLibrary/+/4978
Reviewed-by: TeresaARM <teresa.charlinreyes@arm.com>
Reviewed-by: Michele Di Giorgio <michele.digiorgio@arm.com>
Comments-Addressed: Arm Jenkins <bsgcomp@arm.com>
Tested-by: Arm Jenkins <bsgcomp@arm.com>