Fix intmm benchmark script

[msaroufim]

There were a few bugs in this script that I fixed

Test plan was adding this as a github action

name: Run Benchmarks

on:
  push:
    branches:
      - main
  pull_request:
    branches:
      - main
  workflow_dispatch:

jobs:
  benchmark:
    strategy:
      matrix:
        include:
          - name: CUDA 2.2.2
            runs-on: 4-core-ubuntu-gpu-t4
            torch-spec: 'torch==2.2.2'
          - name: CUDA 2.3 RC
            runs-on: 4-core-ubuntu-gpu-t4
            torch-spec: 'torch==2.3.0 --index-url https://download.pytorch.org/whl/test/cu121'
          - name: CUDA Nightly
            runs-on: 4-core-ubuntu-gpu-t4
            torch-spec: '--pre torch --index-url https://download.pytorch.org/whl/nightly/cu121'
          - name: CPU 2.2.2
            runs-on: 32-core-ubuntu
            torch-spec: 'torch==2.2.2 --index-url https://download.pytorch.org/whl/cpu'
          - name: CPU 2.3 RC
            runs-on: 32-core-ubuntu
            torch-spec: 'torch==2.3.0 --index-url https://download.pytorch.org/whl/test/cpu'
          - name: Nightly CPU
            runs-on: 32-core-ubuntu
            torch-spec: '--pre torch --index-url https://download.pytorch.org/whl/nightly/cpu'
    runs-on: ${{ matrix.runs-on }}
    steps:
    - uses: actions/checkout@v2

    - name: Set up Python
      uses: actions/setup-python@v2
      with:
        python-version: '3.9'

    - name: Install dependencies
      run: |
        python -m pip install --upgrade pip
        pip install ${{ matrix.torch-spec }}
        pip install -r requirements.txt
        pip install -r dev-requirements.txt
    - name: Install package
      run: |
        pip install .
    - name: Run benchmark
      run: |
        cd benchmarks
        python intmm.py --file_path intmm_shapes.csv
        python intmm.py --file_path sam_vit_b_shapes.csv