precommit hooks

[ella-goodman]

Summary

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Checklists

This pull/merge request meets the following requirements:

• code runs
• developments are ethical and secure
• you have made proportionate checks that the code works correctly
• test suite passes
• developments adhere to analytical quality assurance plan (see docs/analytical_quality_assurance/analytical_quality_assurance_plan.md)
• data log updated (see docs/analytical_quality_assurance/data_log.md), if necessary
• assumptions, and caveats log updated (see docs/analytical_quality_assurance/assumptions_caveats.md), if
  necessary
• minimum usable documentation written in the docs folder

Comments have been added below around the incomplete checks.