[megatron] fix: Bump Megatron-Bridge commit for PEFT recompute (verl-project#4702)

### What does this PR do?

Resolves:
- verl-project#4063 (comment)
- verl-project#4514

Related to: verl-project#4566


NVIDIA-NeMo/Megatron-Bridge@953aabf

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Signed-off-by: Hollow Man <hollowman@opensuse.org>

Author: HollowMan6

.github/workflows/e2e_ppo_trainer_megatron_vllm.yml

@@ -150,7 +150,7 @@ jobs:
       - name: clean up and install Megatron-Bridge
         run: |
           rm -rf checkpoints
-          pip3 install git+https://github.com/NVIDIA-NeMo/Megatron-Bridge.git@a489bed --no-deps --no-build-isolation
+          pip3 install git+https://github.com/NVIDIA-NeMo/Megatron-Bridge.git@953aabf --no-deps --no-build-isolation
           pip3 install git+https://github.com/NVIDIA/Megatron-LM.git@2d398b4 --no-deps --no-build-isolation
           pip3 install "nvidia-modelopt[torch]>=0.37.0" transformers==4.57.1
       - name: Running GSM8K E2E training tests with 3D parallelism on 8 L20 GPUs with Megatron, use Megatron-Bridge LoRA e2e to pre-load and save (Deepseek)

.github/workflows/e2e_ppo_trainer_megatron_vllm_2.yml

@@ -129,7 +129,7 @@ jobs:
         run: |
           pip3 install -r requirements-test.txt
           pip3 install --no-deps -e .
-          pip3 install git+https://github.com/NVIDIA-NeMo/Megatron-Bridge.git@a489bed --no-deps --no-build-isolation
+          pip3 install git+https://github.com/NVIDIA-NeMo/Megatron-Bridge.git@953aabf --no-deps --no-build-isolation
           pip3 install git+https://github.com/NVIDIA/Megatron-LM.git@2d398b4 --no-deps --no-build-isolation
           pip3 install "nvidia-modelopt[torch]>=0.37.0" transformers==4.57.1
       - name: Prepare GSM8K dataset

docs/advance/ppo_lora.rst

@@ -62,7 +62,7 @@ Megatron Backend Usage Guide
 
 You need to install and enable Megatron-Bridge for Megatron LoRA support.
 
-Make sure you use Megatron-Bridge later than 0.2.0, and we recommended using `this commit <https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/a489bed3a2410ed9b000ec13a3c90176fec7d99c>`_ or later for proper support, and use the following settings to enable Megatron-Bridge:
+Make sure you use Megatron-Bridge later than 0.2.0, and we recommended using `this commit <https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/953aabf75c0500180dc14a6a76cf9e7e7c4baec7>`_ or later for proper support, and use the following settings to enable Megatron-Bridge:
 
 - ``actor_rollout_ref.actor.megatron.use_mbridge=True``
 - ``actor_rollout_ref.actor.megatron.vanilla_mbridge=False``

examples/grpo_trainer/run_qwen2-7b_math_megatron_lora.sh

@@ -3,7 +3,7 @@ set -xeuo pipefail
 
 # Need to install Megatron-Bridge
 # NOTE: Make sure you use Megatron-Bridge later than 0.2.0 
-# (Recommend https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/a489bed3a2410ed9b000ec13a3c90176fec7d99c or later)
+# (Recommend https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/953aabf75c0500180dc14a6a76cf9e7e7c4baec7 or later)
 # for proper MoE LoRA support.
 
 # For Megatron communication/computation overlapping

examples/grpo_trainer/run_qwen3moe-30b_megatron_lora.sh

@@ -3,7 +3,7 @@ set -xeuo pipefail
 
 # Need to install Megatron-Bridge
 # NOTE: Make sure you use Megatron-Bridge later than 0.2.0 
-# (Recommend https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/a489bed3a2410ed9b000ec13a3c90176fec7d99c or later)
+# (Recommend https://github.com/NVIDIA-NeMo/Megatron-Bridge/commit/953aabf75c0500180dc14a6a76cf9e7e7c4baec7 or later)
 # for proper MoE LoRA support.
 
 # For Megatron communication/computation overlapping