(sit-for): Remove support for old calling convention

* lisp/subr.el (sit-for): Remove support for old calling convention

* doc/lispref/functions.texi (Obsolete Functions): Adjust wording now
that we don't support `sit-for`s old convention any more.
* doc/lispref/commands.texi (Waiting): Remove mention of old calling
convention for `sit-for`.
10 jobs for master in 295 minutes and 12 seconds (queued for 6 seconds)
Status Job ID Name Coverage
  Build Images
passed #75448
build-image-inotify

00:55:09

 
  Normal
failed #75449
test-all-inotify

04:00:03

 
  Platform Images
failed #75450
build-image-eglot

00:03:10

failed #75452
build-image-gnustep

00:02:58

passed #75451
build-image-tree-sitter

00:55:00

 
  Platforms
skipped #75453
test-eglot
skipped #75455
test-gnustep
passed #75454
test-tree-sitter

00:01:30

 
  Native Comp Images
failed #75456
build-native-comp-speed2

00:02:57

 
  Native Comp
skipped #75457
test-native-comp-speed2
 
Name Stage Failure
failed
test-all-inotify Normal The script exceeded the maximum execution time set for the job
Loading em-term...
Loading em-unix...
timeout: the monitored command dumped core
make[3]: *** [Makefile:181: lisp/eshell/esh-io-tests.log] Error 124
ELC lisp/eshell/esh-opt-tests.elc
GEN lisp/eshell/esh-opt-tests.log
ELC lisp/eshell/esh-proc-tests.elc
GEN lisp/eshell/esh-proc-tests.log
ERROR: Job failed: execution took longer than 4h0m0s seconds

failed
build-image-eglot Platform Images
 > [internal] load build context:
------
rpc error: code = Canceled desc = grpc: the client connection is closing
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-eglot-9ecb595d: No such file or directory
ERROR: Job failed: exit code 1
failed
build-image-gnustep Platform Images
 > [internal] load build context:
------
rpc error: code = Canceled desc = grpc: the client connection is closing
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-9ecb595d: No such file or directory
ERROR: Job failed: exit code 1
failed
build-native-comp-speed2 Native Comp Images
rpc error: code = Unavailable desc = transport is closing
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-native-comp-speed2-9ecb595d: No such file or directory
Cleaning up project directory and file based variables
ERROR: Job failed: exit code 1