[CoreML EP] Add ArgMax op support and modify OpBuilder interface (#7924)
* add argmax skip cast op support [initial]
* modify some op support related logic
* fix typo
* add cast node into the partition
* update cast op builder and add int32 graph output
* modify op_builder interface
* exclude unused header file
* clean minor update
* minor change
* address comments
* address more comments
* add UT test for the case
* address more comments
* minor change
* refine
* update
* refine
* make UT test run on CPU
* minor formatting
* update
* switch UT test implementation
* minor refine
Co-authored-by: rachguo <rachguo@rachguos-Mac-mini.local>