gulp-stylelintが反応しません　stylelint: Undefined rule unicode-bom

gulpfile.jsは以下です。

gulpfileJS
1const gulp = require('gulp');
2
3gulp.task('lint-css', function lintCssTask() {
4  const gulpStylelint = require('gulp-stylelint');
5
6  return gulp
7    .src('src/**/*.css')
8    .pipe(gulpStylelint({
9      reporters: [
10        {formatter: 'string', console: true}
11      ]
12    }));
13});

.stylelintrc.jsonは以下です（先頭にピリオドつけています）

stylelintrc
1{
2  "extends": [
3    "stylelint-config-recommended-scss",
4    "stylelint-config-recess-order",
5    "stylelint-prettier/recommended"
6  ]
7}

package.jsonは以下です

packageJSON
1{
2  "name": "gulptest",
3  "version": "1.0.0",
4  "description": "",
5  "main": "index.js",
6  "scripts": {
7    "test": "echo \"Error: no test specified\" && exit 1",
8    "lint:css": "stylelint --fix  ./src/scss/**/*.scss"
9  },
10  "keywords": [],
11  "author": "",
12  "license": "ISC",
13  "devDependencies": {
14    "browser-sync": "^2.26.7",
15    "gulp": "^4.0.2",
16    "gulp-autoprefixer": "^7.0.1",
17    "gulp-cssbeautify": "^2.0.1",
18    "gulp-html-beautify": "^1.0.1",
19    "gulp-notify": "^3.2.0",
20    "gulp-plumber": "^1.2.1",
21    "gulp-pug": "^4.0.1",
22    "gulp-sass": "^4.1.0",
23    "gulp-sass-glob": "^1.1.0",
24    "gulp-stylelint": "^13.0.0",
25    "gulp-uglify": "^3.0.2",
26    "prettier": "^2.0.5",
27    "stylelint": "^13.6.1",
28    "stylelint-config-prettier": "^8.0.2",
29    "stylelint-config-recess-order": "^2.0.4",
30    "stylelint-config-recommended": "^3.0.0",
31    "stylelint-config-recommended-scss": "^4.2.0",
32    "stylelint-config-standard": "^20.0.0",
33    "stylelint-order": "^4.1.0",
34    "stylelint-prettier": "^1.1.2",
35    "stylelint-scss": "^3.18.0"
36  },
37  "browserslist": [
38    "last 2 versions",
39    "Explorer 11",
40    "iOS 9.0",
41    "Android 4.1"
42  ]
43}