ptx: handle duplicate input files

[CrazyRoka]

Description:

Running ptx file file would only output the content of the file once. This caused the GNU test ptx ws.in ws.in | sort | uniq -u to fail (it expects identical output twice, which uniq -u filters out; we were outputting once, so uniq -u printed it).

Input files were stored in a HashMap keyed by filename. The second occurrence of the file overwrote the first.

Fix

Changed the internal FileMap storage to a Vec to preserve the order and multiplicity of input files.

Tests

• Some edge cases intests/ptx/ptx-overrun.sh are now passing correctly.
• Added regression test test_duplicate_input_files in tests/by-util/test_ptx.rs.

[github-actions]

GNU testsuite comparison:

GNU test failed: tests/tty/tty-eof. tests/tty/tty-eof is passing on 'main'. Maybe you have to rebase?

[sylvestre]

sorry, it needs to be rebased, thanks

[github-actions]

GNU testsuite comparison:

Skipping an intermittent issue tests/tty/tty-eof (passes in this run but fails in the 'main' branch)

[ChrisDryden]

Rebasing to show tracking that the ptx gnu integ test will be passing now after this pr, kudos!

[github-actions]

GNU testsuite comparison:

Skip an intermittent issue tests/shuf/shuf-reservoir (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/sort/sort-stale-thread-mem (fails in this run but passes in the 'main' branch)
Skip an intermittent issue tests/tail/follow-name (fails in this run but passes in the 'main' branch)
Congrats! The gnu test tests/ptx/ptx-overrun is no longer failing!

[sylvestre]

Congrats! The gnu test tests/ptx/ptx-overrun is no longer failing!

well done :)