docs: add section to describe how to reduce build size

[unix]

Checklist

• Fix linting errors
• Tests have been added / updated (or snapshots)

Change information

[netlify]

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🔨 Explore the source changes: 1df3530

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[codecov]

Codecov Report

Merging #748 (1df3530) into master (e7be5d9) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #748   +/-   ##
=======================================
  Coverage   98.85%   98.85%           
=======================================
  Files         198      198           
  Lines        3045     3045           
  Branches      669      669           
=======================================
  Hits         3010     3010           
  Misses         34       34           
  Partials        1        1           

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