Update dependency postcss-loader to v6 (#4415)

Co-authored-by: Renovate Bot <bot@renovateapp.com>

package.json

@@ -98,7 +98,7 @@
     "nyc": "15.1.0",
     "postcss": "8.4.4",
     "postcss-import": "14.0.2",
-    "postcss-loader": "5.3.0",
+    "postcss-loader": "6.2.1",
     "postcss-preset-env": "7.0.1",
     "prettier": "2.2.1",
     "pretty-quick": "3.1.2",

yarn.lock

@@ -4819,10 +4819,10 @@ kind-of@^6.0.2, kind-of@^6.0.3:
   resolved "https://registry.yarnpkg.com/kind-of/-/kind-of-6.0.3.tgz#07c05034a6c349fa06e24fa35aa76db4580ce4dd"
   integrity sha512-dcS1ul+9tmeD95T+x28/ehLgd9mENa3LsvDTtzm3vyBEO7RPptvAD+t44WVXaUjTBRcrpFeFlC8WCruUR456hw==
 
-klona@^2.0.4:
-  version "2.0.4"
-  resolved "https://registry.yarnpkg.com/klona/-/klona-2.0.4.tgz#7bb1e3affb0cb8624547ef7e8f6708ea2e39dfc0"
-  integrity sha512-ZRbnvdg/NxqzC7L9Uyqzf4psi1OM4Cuc+sJAkQPjO6XkQIJTNbfK2Rsmbw8fx1p2mkZdp2FZYo2+LwXYY/uwIA==
+klona@^2.0.5:
+  version "2.0.5"
+  resolved "https://registry.yarnpkg.com/klona/-/klona-2.0.5.tgz#d166574d90076395d9963aa7a928fabb8d76afbc"
+  integrity sha512-pJiBpiXMbt7dkzXe8Ghj/u4FfXOOa98fPW+bihOJ4SjnoijweJrNThJfd3ifXpXhREjpoF2mZVH1GfS9LV3kHQ==
 
 known-css-properties@^0.21.0:
   version "0.21.0"
@@ -6171,14 +6171,14 @@ postcss-less@^3.1.4:
   dependencies:
     postcss "^7.0.14"
 
-postcss-loader@5.3.0:
-  version "5.3.0"
-  resolved "https://registry.yarnpkg.com/postcss-loader/-/postcss-loader-5.3.0.tgz#1657f869e48d4fdb018a40771c235e499ee26244"
-  integrity sha512-/+Z1RAmssdiSLgIZwnJHwBMnlABPgF7giYzTN2NOfr9D21IJZ4mQC1R2miwp80zno9M4zMD/umGI8cR+2EL5zw==
+postcss-loader@6.2.1:
+  version "6.2.1"
+  resolved "https://registry.yarnpkg.com/postcss-loader/-/postcss-loader-6.2.1.tgz#0895f7346b1702103d30fdc66e4d494a93c008ef"
+  integrity sha512-WbbYpmAaKcux/P66bZ40bpWsBucjx/TTgVVzRZ9yUO8yQfVBlameJ0ZGVaPfH64hNSBh63a+ICP5nqOpBA0w+Q==
   dependencies:
     cosmiconfig "^7.0.0"
-    klona "^2.0.4"
-    semver "^7.3.4"
+    klona "^2.0.5"
+    semver "^7.3.5"
 
 postcss-logical@^5.0.0:
   version "5.0.0"