Improve the raise-sexp doc string

* lisp/emacs-lisp/lisp.el (raise-sexp): Try to explain what the
command does (bug#55788).
2 jobs for master in 60 minutes and 21 seconds (queued for 1 second)
Status Job ID Name Coverage
  Build Images
failed #46793
build-image-inotify

01:00:21

 
  Normal
skipped #46794
test-lisp-emacs-lisp-inotify
 
Name Stage Failure
failed
build-image-inotify Build Images
------
executor failed running [/bin/sh -c make bootstrap]: exit code: 2
Running after_script
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-inotify-b3dc23dd: No such file or directory
Cleaning up file based variables
ERROR: Job failed: exit code 1