bug#56110: 27+; switching from line-mode to char-mode

[C. Michailidis]

I recently updated a few machines and noticed that term.el in Emacs
version 27+ forcibly submits my pasted commands to the shell sub-process
when switching to char-mode (from line-mode). In prior versions of Emacs
term.el didn't do this; I could further modify the command in char-mode
even if it was pasted from line-mode and submit it myself by pressing
enter.

See also:
https://lists.gnu.org/archive/html/help-gnu-emacs/2022-06/msg00452.html