fix llama2_70b_lora broken link for Accelerate config file in the readme

[hiwotadese]

No description provided.

[github-actions]

MLCommons CLA bot:
Thank you very much for your submission, we really appreciate it. Before we can accept your contribution, we ask that you sign the MLCommons CLA (Apache 2). Please use this [Google form] (https://forms.gle/Ew1KkBVpyeJDuRw67) to initiate authorization. If you are from an MLCommons member organization, we will request that you be added to the CLA. If you are not from a member organization, we will email you a CLA to sign. For any questions, please contact support@mlcommons.org.
0 out of 1 committers have signed the MLCommons CLA.
❌ @Hiwot Kassa
Hiwot Kassa seems not to be a GitHub user. You need a GitHub account after you become MLCommons member. If you have already a GitHub account, please add the email address used for this commit to your account.
_{You can retrigger this bot by commenting recheck in this Pull Request}

[ShriyaPalsamudram]

@hiwotadese can you also set gradient_clipping: 0.3 in the config?
Details are in #765

[hiwotadese]

@ShriyaPalsamudram the config file here https://github.com/mlcommons/training/blob/master/llama2_70b_lora/configs/default_config.yaml already have the gradient_clipping: 0.3

[hiwotadese]

recheck