Fixup for bug#51037

* lisp/emacs-lisp/ert.el (ert-batch-backtrace-line-length): Fix
docstring.
(ert-run-tests-batch): Remove redundand let-binding.
(ert-run-tests-interactively): Fix interactive spec.
3 jobs for master in 100 minutes and 2 seconds (queued for 170 minutes and 31 seconds)
Status Job ID Name Coverage
  Build Images
failed #32976
build-image-inotify

01:26:44

 
  Normal
passed #32977
test-lisp-inotify

00:11:59

passed #32978
test-lisp-net-inotify

00:08:51

 
Name Stage Failure
failed
build-image-inotify Build Images
#12 ERROR: executor failed running [/bin/sh -c make bootstrap]: exit code: 2
------
> [emacs-inotify 5/5] RUN make bootstrap:
------
executor failed running [/bin/sh -c make bootstrap]: exit code: 2
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}
ERROR: Job failed: exit code 1