text: Title: config: support checkout_jobs
  Body: # Bug Report
  
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  checkout: slow checkouts
  
  ## Description
  
  <!--
  A clear and concise description of what the bug is.
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  Checkout copies all files in parallel, leading to disk saturation, and excessive checkout times. E.g. At this time, `lsof` for the dvc process shows 331 files open.
  
  ### Reproduce
  
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  Step list of how to reproduce the bug
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  dvc pull
  
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  2. Copy dataset.zip to the directory
  3. dvc add dataset.zip
  4. dvc run -d dataset.zip -o model ./train.sh
  5. modify dataset.zip
  6. dvc repro
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  ### Expected
  
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  Parallelization in moderation, respecting the jobs: parameter in .dvc/config, or some similar parameter.
  
  ### Environment information
  
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  This is required to ensure that we can reproduce the bug.
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  **Output of `dvc doctor`:**
  
  ```console
  $ dvc doctor
  DVC version: 3.11.1 (pip)
  -------------------------
  Platform: Python 3.10.10 on Linux-6.1.0-11-amd64-x86_64-with-glibc2.36
  Subprojects:
  	dvc_data = 2.10.1
  	dvc_objects = 0.24.1
  	dvc_render = 0.5.3
  	dvc_task = 0.3.0
  	scmrepo = 1.1.0
  Supports:
  	http (aiohttp = 3.8.5, aiohttp-retry = 2.8.3),
  	https (aiohttp = 3.8.5, aiohttp-retry = 2.8.3),
  	ssh (sshfs = 2023.7.0)
  Config:
  	Global: /home/john/.config/dvc
  	System: /etc/xdg/dvc
  ```
  
  **Additional Information (if any):**
  
  https://discuss.dvc.org/t/is-jobs-n-ignored-on-local-stores/1768
  
  
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