style: read without -r will mangle backslashes

[mboersma]

Reason for Change:
Warns about read interpreting backslashes by default in unexpected ways.

See https://github.com/koalaman/shellcheck/wiki/SC2162

Issue Fixed:
Refs #953

Requirements:

• uses conventional commit messages
• includes documentation
• adds unit tests
• tested upgrade from previous version

Notes:

[codecov]

Codecov Report

Merging #1790 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #1790   +/-   ##
=======================================
  Coverage   76.39%   76.39%           
=======================================
  Files         130      130           
  Lines       19351    19351           
=======================================
  Hits        14783    14783           
  Misses       3771     3771           
  Partials      797      797

[jackfrancis]

/lgtm

[acs-bot]

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