fix: convert_dcp_to_hf.py correctly loads saved tokenizer from DCP if detected

[trias702]

What does this PR do ?

Fixed convert_dcp_to_hf.py to load the tokenizer directory when detected.

Usage

• You can potentially add a usage example below

uv run python examples/converters/convert_dcp_to_hf.py --config /path/to/config.yaml --dcp-ckpt-path /path/to/policy/weights --hf-ckpt-path /path/to/hf

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[yuki-97]

@RayenTian could you help to take a review?

[RayenTian]

@trias702 Thanks a lot for adding this! lgtm!
CC: @yuki-97

[yuki-97]

hi @trias702 , thanks for helping fix this! left some minor comments.

[yuki-97]

/ok to test 698757c

[yuki-97]

hi @trias702 , there's a lint check fail, could you help to fix?

[trias702]

hi @trias702 , there's a lint check fail, could you help to fix?

Sorry, I don't understand why it's failing. I'm afraid I don't know much about linting or how it works.