docs: replace Greek 'μ' with micro 'µ' again

[ddcc4]

Overview

Follow-up to PR #17331: Unicode has 2 different characters for mu:

• µ (U+00B5) is the "micro" symbol, meaning 1/1,000,000th.
• μ (U+03BC) is for writing Greek-language text.

Using the Greek-language μ can cause ugly font fallback if a font doesn't have the Greek alphabet.

We cleaned this all up last year, but since then, new Greek μs have snuck into our codebase, mostly in the docs and release notes.

Test Plan and Hands on Testing

Run CI tests.

Risk assessment

Low.

I'm adding this in RS 8.8.0 branch because the release notes are in RS 8.8.0.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 26.53%. Comparing base (c2a71c8) to head (b2a1268).
⚠️ Report is 2 commits behind head on chore_release-8.8.0.

Additional details and impacted files

@@                 Coverage Diff                  @@
##           chore_release-8.8.0   #20308   +/-   ##
====================================================
  Coverage                26.53%   26.53%           
====================================================
  Files                     3542     3542           
  Lines                   296577   296577           
  Branches                 43417    43417           
====================================================
  Hits                     78690    78690           
  Misses                  217855   217855           
  Partials                    32       32           

Flag	Coverage Δ
protocol-designer	18.66% <ø> (ø)

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[jerader]

oh noooo haha thanks for fixing

[sfoster1]

can we add a lint rule for this? could even be a CI or makefile task that literally runs grep $'\u03BC'

[ddcc4]

can we add a lint rule for this? could even be a CI or makefile task that literally runs grep $'\u03BC'

Yeah. It requires a small bit of human judgement though that might be hard to automate -- e.g., the lint rule would have to ignore non-human-text files. And last time I did this, I was told that we didn't want to update any snapshot files, even if they contain the wrong character, because the snapshots are supposed to reflect files that are out there, warts and all.

[ecormany]

I would be happy to run such a lint on the /docs directory.