Changed command line argpasrse to process '--symmetric [True|False]'. (#19577)
### Description
<!-- Describe your changes. -->
Accept the command line option --symmetric and its optional value
correctly. If the optional value matches uncased to 'True' then set
symmetric to True else set symmetric to False. Asymmetric quantization
will generate zero_point input.
```
usage: matmul_4bits_quantizer.py [-h] --input_model INPUT_MODEL --output_model OUTPUT_MODEL [--block_size BLOCK_SIZE] [--symmetric [{True,False}]] [--accuracy_level ACCURACY_LEVEL] [-v]
[--nodes_to_exclude NODES_TO_EXCLUDE [NODES_TO_EXCLUDE ...]]
```
### Motivation and Context
<!-- - Why is this change required? What problem does it solve?
- If it fixes an open issue, please link to the issue here. -->