sed: discard text queued by a, r and R on Q, as GNU sed does

[DePasqualeOrg]

Q quits without printing the pattern space, and GNU sed also discards any text that a, r or R queued in the same cycle. uutils sed writes that text: printf 'x\n' | sed -e 'a A' -e Q prints A, while GNU sed prints nothing. This PR clears the queue on Q. q still writes queued text, as in GNU sed.

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 94.82%. Comparing base (3676eac) to head (840add2).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #594   +/-   ##
=======================================
  Coverage   94.82%   94.82%           
=======================================
  Files          14       14           
  Lines        7212     7213    +1     
  Branches      428      428           
=======================================
+ Hits         6839     6840    +1     
  Misses        372      372           
  Partials        1        1           

Flag	Coverage Δ
macos_latest	96.37% <100.00%> (+<0.01%)	⬆️
ubuntu_latest	96.31% <100.00%> (+<0.01%)	⬆️
windows_latest	0.00% <0.00%> (ø)

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[codspeed]

Merging this PR will regress 1 benchmark

⚡ 7 improved benchmarks
❌ 1 regressed benchmark
✅ 3 untouched benchmarks

Warning

Please fix the performance issues or acknowledge them on CodSpeed.

Performance Changes

	Benchmark	BASE	HEAD	Efficiency
❌	access_log_translit	999.6 ms	1,024.7 ms	-2.45%
⚡	no_op_short	2.4 s	2.2 s	+10.64%
⚡	access_log_no_op	1.7 s	1.6 s	+7.44%
⚡	access_log_append	1.5 s	1.4 s	+2.99%
⚡	access_log_no_del	1.1 s	1.1 s	+2.38%
⚡	access_log_no_subst	1.1 s	1.1 s	+2.38%
⚡	remove_cr	518.6 ms	506.5 ms	+2.38%
⚡	access_log_all_del	1.1 s	1.1 s	+2.31%

Tip

Investigate this regression by commenting @codspeedbot fix this regression on this PR, or directly use the CodSpeed MCP with your agent.

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_{Comparing DePasqualeOrg:fix-q-discards-appends (f2ac3ee) with main (479c4be)}

[sylvestre]

please use the test_ prefix like the other tests