CI: Apply --diff-filter=d to all diff calls

.ci/helper.sh

@@ -33,13 +33,14 @@ get_translators_to_check() {
 	# when running from a local development PR branch
 	#
 	# The branching point hash retrieval logic is based on https://stackoverflow.com/a/12185115/3199106
+	#
+	# We get the set of modified files with git diff, passing --diff-filter=d to exclude deleted files.
 
 	TRANSLATORS_TO_CHECK=""
 
 	# Push to master
 	if [ "${GITHUB_REF:-}" = "refs/heads/master" ]; then
 		before_commit=$(jq -r '.before' $(echo $GITHUB_EVENT_PATH))
-		# --diff-filter=d: Exclude deleted files
 		TRANSLATORS_TO_CHECK=$(git diff $before_commit --name-only --diff-filter=d | { grep -e "^[^/]*.js$" || true; })
 	# Pull request
 	else
@@ -50,11 +51,11 @@ get_translators_to_check() {
 		if [ $num_parent_commits -gt 1 ]; then
 			first_parent=$(git rev-list --first-parent ^master HEAD^2 | tail -n1)
 			branch_point=$(git rev-list "$first_parent^^!")
-			TRANSLATORS_TO_CHECK=$(git diff HEAD^2 $branch_point --name-only | { grep -e "^[^/]*.js$" || true; })
+			TRANSLATORS_TO_CHECK=$(git diff HEAD^2 $branch_point --name-only --diff-filter=d | { grep -e "^[^/]*.js$" || true; })
 		else
 			first_parent=$(git rev-list --first-parent ^master HEAD | tail -n1)
 			branch_point=$(git rev-list "$first_parent^^!")
-			TRANSLATORS_TO_CHECK=$(git diff $branch_point --name-only | { grep -e "^[^/]*.js$" || true; })
+			TRANSLATORS_TO_CHECK=$(git diff $branch_point --name-only --diff-filter=d | { grep -e "^[^/]*.js$" || true; })
 		fi
 	fi
 }