Add docs placeholder checks to lint-release-proposal workflow

[targos]

https://github.com/nodejs/node/blob/main/.github/workflows/lint-release-proposal.yml

So we don't find out later when the release build is triggered on Jenkins.

See

node/Makefile

Lines 1034 to 1044 in 6f084ff

	@if [ "$(DISTTYPE)" = "release" ] && `grep -q REPLACEME doc/api/*.md`; then \
	echo 'Please update REPLACEME tags in the following doc/api/*.md files (See doc/contributing/releases.md):\n' ; \
	REPLACEMES="$(shell grep -l REPLACEME doc/api/*.md)" ; \
	echo "$$REPLACEMES\n" | tr " " "\n" ; \
	exit 1 ; \
	fi
	@if [ "$(DISTTYPE)" = "release" ] && \
	`grep -q DEP...X doc/api/deprecations.md`; then \
	echo 'Please update DEP...X in doc/api/deprecations.md (See doc/contributing/releases.md)' ; \
	exit 1 ; \
	fi

[targos]

Assuming it was fixed by #56251