Use new `pre-commit` script to detect and fix existing `i18n` syntax issues

[rebecca-shoptaw]

Problem

The new detect_missing_i18n script by @pidgezero-one has given us a super helpful list of i18n syntaxing issues throughout the codebase and/or valid i18n that accidentally gets flagged by the script.

These files are listed in EXCLUDE_LIST in detect_missing_i18n.py.

Proposal & Constraints

Once the PR (#9428) is merged, I propose going through the full list of excluded files myself and making any changes where needed, either fixing i18n syntax or adjusting distribution of text to avoid accidental flags of the script. I'll also make any updates to the i18n Developer's Guide where needed as a result of edge-cases I discover in the process.

Related files

detect_missing_i18n.py

Issue phases & sub-PRs

• [ ] Phase 1: Update warn regex to avoid accidentally flagging Python, escape remaining Python files as needed.
  • PR: #9502

Stakeholders

@pidgezero-one

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Instructions for Contributors

• Please run these commands to ensure your repository is up to date before creating a new branch to work on this issue and each time after pushing code to Github, because the pre-commit bot may add commits to your PRs upstream.