ug: lmp-customization: add instruction to escape passwd with printf

[ricardosalveti]

bash printf has an easy way to escape any special character.

Readiness

• Merge (pending reviews)
• Merge after date or event
• Draft

Overview

Facilitate the life of the user creating a custom password.

Checklist

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• Run spelling and grammar check, preferably with linter.
• Avoid changing any header associated with a link/reference.
• Step through instructions (or ask someone to do so).
• Review for wordiness
• Match tone and style of page/section.
• Run make linkcheck.
• View HTML in a browser to check rendering.
• Use semantic newlines.
• follow best practices for commits.
  • Descriptive title written in the imperative.
  • Include brief overview of QA steps taken.
  • Mention any related issues numbers.
  • End message with sign off/DCO line (-s, --signoff).
  • Sign commit with your gpg key (-S, --gpg-sign).
  • Squash commits if needed.
• Request PR review by a technical writer and at least one peer.

[doanac]

Docs for 1ebabaa are browsable at: https://ci.foundries.io/projects/fio-docs/builds/2556/docs/artifacts/html/index.html

[kprosise]

LGTM