swift megatron sys._base_executable problem

[firefighter-eric]

Describe the bug
What the bug is, and how to reproduce, better with screenshots(描述bug以及复现过程，最好有截图)

sudo -E \
    CUDA_VISIBLE_DEVICES=0 \
    MASTER_PORT=12345 NPROC_PER_NODE=1 \
    /mnt/bn/merlin-lq-nas-1/envs/megatron/bin/megatron sft \
    xxx

Using the absolute path to the Megatron command caused Swift to use the system’s base Python.

sys._base_executable = '/root/miniconda3/bin/python3'

Your hardware and system info
Write your system info like CUDA version/system/GPU/torch version here(在这里给出硬件信息和系统信息，如CUDA版本，系统，GPU型号和torch版本等)

cuda=12.4
gpu=1xA100
torch=2.6.0
ms-swift=3.4.0

Additional context
Add any other context about the problem here(在这里补充其他信息)

[firefighter-eric]

Add PATH=/mnt/bn/merlin-lq-nas-1/envs/megatron/bin:$PATH solving this problem
Looking forward to a solution from ms-swift.