Update devDependencies

* @babel/cli                       ^7.14.3  →  ^7.14.8
* @babel/core                      ^7.14.3  →  ^7.14.8
* @babel/preset-env                ^7.14.2  →  ^7.14.8
* @rollup/plugin-commonjs          ^19.0.0  →  ^19.0.1
* @rollup/plugin-node-resolve      ^13.0.0  →  ^13.0.2
* autoprefixer                     ^10.2.5  →  ^10.3.1
* eslint                           ^7.26.0  →  ^7.31.0
* eslint-config-xo                 ^0.36.0  →  ^0.37.0
* eslint-plugin-import             ^2.23.2  →  ^2.23.4
* eslint-plugin-unicorn            ^31.0.0  →  ^34.0.1
* globby                           ^11.0.3  →  ^11.0.4
* hugo-bin                         ^0.71.1  →  ^0.73.0
* karma                             ^6.3.2  →   ^6.3.4
* karma-firefox-launcher            ^2.1.0  →   ^2.1.1
* linkinator                       ^2.13.6  →  ^2.14.0
* nodemon                           ^2.0.7  →   ^2.0.12
* node-sass                         ^6.0.0  →   ^6.0.1
* postcss                           ^8.3.0  →   ^8.3.5
* qunit                            ^2.15.0  →  ^2.16.0
* rollup                           ^2.48.0  →  ^2.53.3
* stylelint-config-twbs-bootstrap   ^2.2.0  →   ^2.2.3
* vnu-jar                           21.4.9  →  21.6.11

.eslintrc.json

@@ -8,7 +8,12 @@
     "xo/browser"
   ],
   "rules": {
+    "arrow-body-style": "off",
     "capitalized-comments": "off",
+    "comma-dangle": [
+      "error",
+      "never"
+    ],
     "indent": [
       "error",
       2,
@@ -34,6 +39,10 @@
       "error",
       "always"
     ],
+    "operator-linebreak": [
+      "error",
+      "after"
+    ],
     "semi": [
       "error",
       "never"
@@ -42,11 +51,14 @@
     "unicorn/explicit-length-check": "off",
     "unicorn/no-array-callback-reference": "off",
     "unicorn/no-array-for-each": "off",
+    "unicorn/no-array-method-this-argument": "off",
     "unicorn/no-for-loop": "off",
     "unicorn/no-null": "off",
     "unicorn/no-unused-properties": "error",
     "unicorn/no-useless-undefined": "off",
+    "unicorn/numeric-separators-style": "off",
     "unicorn/prefer-array-find": "off",
+    "unicorn/prefer-array-flat": "off",
     "unicorn/prefer-dom-node-append": "off",
     "unicorn/prefer-dom-node-dataset": "off",
     "unicorn/prefer-dom-node-remove": "off",
@@ -55,6 +67,7 @@
     "unicorn/prefer-module": "off",
     "unicorn/prefer-number-properties": "off",
     "unicorn/prefer-optional-catch-binding": "off",
+    "unicorn/prefer-prototype-methods": "off",
     "unicorn/prefer-query-selector": "off",
     "unicorn/prefer-reflect-apply": "off",
     "unicorn/prefer-set-has": "off",