Bump Flax version for latest JAX compatibility

[bvandermoon]

Description

Bump Flax version to support latest JAX nightly. I was seeing this error for a nightly benchmark runner workload which is tied to JAX/Flax incompatibility: TypeError: ShapedArray.__init__() got an unexpected keyword argument 'vma'

Note that we need to generate a clean seed-env run soon. Not doing that here since all MaxText APIs are not currently compatible with the latest JAX version

Tests

build_maxtext_docker_image MODE=stable
python3 -m benchmarks.benchmark_runner xpk \
    --project=tpu-prod-env-one-vm \
    --zone=southamerica-west1 \
    --device_type=v6e-256 \
    --num_slices=1  \
    --cluster_name=$CLUSTER_NAME \
    --base_output_directory=$BASE_OUTPUT_DIRECTORY \
    --model_name="llama3_1_70b_8192" \
    --base_docker_image=maxtext_base_image

build_maxtext_docker_image MODE=nightly
python3 -m benchmarks.benchmark_runner xpk \
    --project=tpu-prod-env-one-vm \
    --zone=southamerica-west1 \
    --device_type=v6e-256 \
    --num_slices=1  \
    --cluster_name=$CLUSTER_NAME \
    --base_output_directory=$BASE_OUTPUT_DIRECTORY \
    --model_name="llama3_1_70b_8192" \
    --base_docker_image=maxtext_base_image

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[codecov]

Codecov Report

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