fix spurious failure in run-gnu-testsuite.sh

[e-kwsm]

• correct input and expected output strings
  use ANSI-C strings to interpret \n
• unquote sed_script

sed/util/run-gnu-testsuite.sh

Line 304 in c6479b4

run_sed_test "print_line" "-n 2p" "line1\nline2\nline3" "line2" "-n"

requires to unquote options:

--- main
+++ this PR
- ./target/release/sed -n '-n 2p' input.txt
+ ./target/release/sed -n -n 2p input.txt

Note that print_line still fails due to multiple -n.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 82.11%. Comparing base (c6479b4) to head (fc39ff7).
⚠️ Report is 3 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #268   +/-   ##
=======================================
  Coverage   82.11%   82.11%           
=======================================
  Files          13       13           
  Lines        5327     5327           
  Branches      294      294           
=======================================
  Hits         4374     4374           
  Misses        951      951           
  Partials        2        2           

Flag	Coverage Δ
macos_latest	82.54% <ø> (ø)
ubuntu_latest	82.66% <ø> (ø)
windows_latest	0.00% <ø> (ø)

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[github-actions]

GNU sed testsuite comparison:

Test results comparison:
  Current:   TOTAL: 64 / PASSED: 15 / FAILED: 49 / SKIPPED: 0
  Reference: TOTAL: 64 / PASSED: 8 / FAILED: 56 / SKIPPED: 0

Changes from main branch:
  TOTAL: +0
  PASSED: +7
  FAILED: -7

Test improvements (7):
  + append
  + delete_line
  + delete_range
  + insert
  + line_address
  + range_address
  + word_class

[sylvestre]

oh nice :)