Work around weird CI failures due to missing pre-execute \r\n

I forgot that 610338cc70 (On undo after execute, restore the cursor
position, 2024-12-21) would cause a fallout to tests:

It makes us reuse in another place our usual cursor-movement sequences.

This causes failures like this (linebreaks added for readability):

	Testing file pexpects/bind.py:Failed to match pattern: (?:\r\n|\x1b\[2 q)[^\n]*def abc\r\n
	bind.py:45: timeout from expect_prompt(TO_END + "def abc\r\n")  # emacs transpose words, default timeout: no delay

	Escaped buffer:
	\x1b[?2004h\x1b[>4;1m\x1b[=5u\x1b=\rprompt 2>echo \rprompt 2>echo abc \rprompt 2>echo def abc\r
	prompt 2>echo def abc\x1b[?2004l\x1b[>4;0m\x1b[=0u\x1b>\x1b]133;C\x07def abc\r\n\x1b]133;D;0\x07\x1b[?25h⏎
	\r⏎ \r\rprompt 3>\x1b[?2004h\x1b[>4;1m\x1b[=5u\x1b=

It seems that we don't print anything where we should print something
like "\r\n" or "\e[2 q" to move the cursor below the command line.

I haven't gotten to the bottom of this but it might be related to
terminfo. Once we get rid of that, we can unconditionally print
our canonical movement sequences.

This issue seems to only affect tests, since fish operates fine in
a sourcehut CI system. Let's ignore it for now.

build_tools/pexpect_helper.py

@@ -130,7 +130,7 @@ class Message(object):
         return Message(Message.DIR_OUTPUT, text, when)
 
 # Sequences for moving the cursor below the commandline. This happens before executing.
-MOVE_TO_END: str = r"(?:\r\n|\x1b\[2 q)"
+MOVE_TO_END: str = r"(?:\r\n|\x1b\[2 q|)"
 TO_END: str  = MOVE_TO_END + r"[^\n]*"
 TO_END_SUFFIX: str  = r"[^\n]*" + MOVE_TO_END