Bump 3rdparty/Megatron-LM from 0e85db5 to 2a9793d (NVIDIA#675)

Bumps [3rdparty/Megatron-LM](https://github.com/NVIDIA/Megatron-LM) from
`0e85db5` to `2a9793d`.
<details>
<summary>Commits</summary>
<ul>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/2a9793d19e3a5c0a557c899ad4b902302bbf5fdf"><code>2a9793d</code></a>
Merge branch 'ko3n1g/ci/update-nightly-values' into 'main'</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/60166922d37354f6e0db5baa90821891bc276717"><code>6016692</code></a>
ADLR/megatron-lm!2618 - test: Update nightly values</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/33668156a30cd39579b657f73137a12ddafe0fcc"><code>3366815</code></a>
Merge branch 'xiny/fix_dist_ckpt_for_fp8_padding' into 'main'</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/68589ec319ee73ff6f12f3185143f0e673ae5e25"><code>68589ec</code></a>
ADLR/megatron-lm!2529 - Fix distributed checkpointing for fp8
padding/unpadding</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/eedb2fe3fdf646d5b222a60fd938c9d9db82a12c"><code>eedb2fe</code></a>
Merge branch 'inference_pipeline_parallelism_fix' into 'main'</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/65084040cd7575dd66bdf14d3cdafa6386e8c84e"><code>6508404</code></a>
ADLR/megatron-lm!2614 - Fix pipeline parallelism bugs in MCore
inference</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/ea94163be72d77f12e7e483fff603961bed936e8"><code>ea94163</code></a>
Merge branch 'MLA_TP' into 'main'</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/4d4676e7954997c3f9a0dc8cee8007950b87e29f"><code>4d4676e</code></a>
ADLR/megatron-lm!2328 - Add support of TP for MLA</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/04f934470e2dc4909b407e487ec3004aa0252bde"><code>04f9344</code></a>
Merge branch 'pmannan/llava_cp' into 'main'</li>
<li><a
href="https://github.com/NVIDIA/Megatron-LM/commit/6e84ec7b5b123fbb9473f89fff6d1a1c06258dad"><code>6e84ec7</code></a>
ADLR/megatron-lm!2504 - Simplify CP in LLaVA and move packed
sequence/padding...</li>
<li>Additional commits viewable in <a
href="https://github.com/NVIDIA/Megatron-LM/compare/0e85db539cf16816ffced6e7dac644d91ffadc04...2a9793d19e3a5c0a557c899ad4b902302bbf5fdf">compare
view</a></li>
</ul>
</details>
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