[SPIR-V] reqd_work_group_size and work_group_size_hint metadata are correctly...

[SPIR-V] reqd_work_group_size and work_group_size_hint metadata are correctly converted to the LocalSize and LocalSizeHint execution mode (#92552)

The goal of this PR is to ensure that reqd_work_group_size and
work_group_size_hint metadata are correctly converted to the LocalSize
and LocalSizeHint execution mode.

reqd_work_group_size and work_group_size_hint require 3 operands (see
https://registry.khronos.org/SPIR-V/specs/unified1/SPIRV.html#Execution_Mode),
if metadata contains less operands, just add a default value (1).