OSH too lenient in parsing the ! operator, e.g. ! true | ! false

[andychu]

from https://gist.github.com/izabera/7dcece1d6df9063d43d2b3b0a222e7bb

https://lobste.rs/s/hv0agk/short_bash_quiz

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mksh is also too lenient, but other shells agree with bash

$ bash -n -c 'true | ! false; echo $?'
bash: -c: line 1: syntax error near unexpected token `!'
bash: -c: line 1: `true | ! false; echo $?'


andy@hoover:~/git/oilshell/oil$ mksh -n -c 'true | ! false; echo $?'


andy@hoover:~/git/oilshell/oil$ yash -n -c 'true | ! false; echo $?'
yash -c:1: syntax error: `!' cannot be used as a command name


andy@hoover:~/git/oilshell/oil$ bin/osh -n -c 'true | ! false; echo $?'
(command.CommandList
  children: [
    (command.Sentence