Fix behavior of Eshell prompt when yanking output into it

* lisp/eshell/esh-util.el (eshell--unmark-string-as-output): New
function...

* lisp/eshell/esh-mode.el (eshell-mode): ... use it.

* test/lisp/eshell/eshell-tests.el (eshell-test/yank-output): New test
(bug#66469).
10 jobs for master in 230 minutes and 17 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Build Images
failed #75356
build-image-inotify

02:50:33

 
  Normal
skipped #75357
test-all-inotify
 
  Platform Images
passed #75358
build-image-eglot

02:52:34

failed #75360
build-image-gnustep

00:57:31

passed #75359
build-image-tree-sitter

02:52:43

 
  Platforms
passed #75361
test-eglot

00:03:49

skipped #75363
test-gnustep
passed #75362
test-tree-sitter

00:02:59

 
  Native Comp Images
passed #75364
build-native-comp-speed2

02:58:57

 
  Native Comp
failed #75365
test-native-comp-speed2

00:51:15

 
Name Stage Failure
failed
test-native-comp-speed2 Native Comp
$ find ${test_name} ! \( -name "*.log" -o -name ${EMACS_TEST_JUNIT_REPORT} \) -type f -delete
$ find ${test_name} -type d -depth -exec rmdir {} + 2>/dev/null
Uploading artifacts...
test-native-comp-speed2-60f69528/: found 531 matching files
Uploading artifacts to coordinator... ok
id=75365 responseStatus=201 Created token=bU3qjrmm
Uploading artifacts...
test-native-comp-speed2-60f69528/junit-test-report.xml: found 1 matching files

Uploading artifacts to coordinator... ok
id=75365 responseStatus=201 Created token=bU3qjrmm
ERROR: Job failed: exit code 2
failed
build-image-inotify Build Images
a16f2e2c60f0: Pushed
e8fe369898c6: Pushed
context deadline exceeded (Client.Timeout exceeded while awaiting headers)
Running after script...
$ test -n "$(docker ps -aq -f name=${test_name})" && docker cp ${test_name}:checkout/test ${test_name}
$ test -n "$(docker ps -aq -f name=${test_name})" && docker rm ${test_name}
find: build-image-inotify-60f69528: No such file or directory
$ find ${test_name} ! \( -name "*.log" -o -name ${EMACS_TEST_JUNIT_REPORT} \) -type f -delete
ERROR: Job failed: exit code 1
failed
build-image-gnustep Platform Images
#12 2319. /usr/include/GNUstep/AppKit/NSToolbarItem.h:128:56: warning: this use of "defined" may not be portable [-Wexpansion-to-defined]
#12 2319. 128 | #if OS_API_VERSION(MAC_OS_X_VERSION_10_4, GS_API_LATEST)
#12 2319. | ^
#12 2319. In file included from /usr/include/GNUstep/AppKit/AppKit.h:23
Running after script...
$ test -n "$(docker ps -aq -f name=${test_name})" && docker cp ${test_name}:checkout/test ${test_name}
$ test -n "$(docker ps -aq -f name=${test_name})" && docker rm ${test_name}
$ find ${test_name} ! \( -name "*.log" -o -name ${EMACS_TEST_JUNIT_REPORT} \) -type f -delete
find: build-image-gnustep-60f69528: No such file or directory
ERROR: Job failed: exit code 1