Bump mini-css-extract-plugin from 1.3.6 to 1.3.8 (#15761)

Bumps [mini-css-extract-plugin](https://github.com/webpack-contrib/mini-css-extract-plugin) from 1.3.6 to 1.3.8.
- [Release notes](https://github.com/webpack-contrib/mini-css-extract-plugin/releases)
- [Changelog](https://github.com/webpack-contrib/mini-css-extract-plugin/blob/master/CHANGELOG.md)
- [Commits](https://github.com/webpack-contrib/mini-css-extract-plugin/compare/v1.3.6...v1.3.8)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

package.json

@@ -111,7 +111,7 @@
     "lodash": "^4.17.19",
     "mark-loader": "^0.1.6",
     "marky": "^1.2.1",
-    "mini-css-extract-plugin": "^1.3.6",
+    "mini-css-extract-plugin": "^1.3.8",
     "mkdirp": "^1.0.4",
     "npmlog": "^4.1.2",
     "object-assign": "^4.1.1",

yarn.lock

@@ -7038,10 +7038,10 @@ min-indent@^1.0.0:
   resolved "https://registry.yarnpkg.com/min-indent/-/min-indent-1.0.1.tgz#a63f681673b30571fbe8bc25686ae746eefa9869"
   integrity sha512-I9jwMn07Sy/IwOj3zVkVik2JTvgpaykDZEigL6Rx6N9LbMywwUSMtxET+7lVoDLLd3O3IXwJwvuuns8UB/HeAg==
 
-mini-css-extract-plugin@^1.3.6:
-  version "1.3.6"
-  resolved "https://registry.yarnpkg.com/mini-css-extract-plugin/-/mini-css-extract-plugin-1.3.6.tgz#02e2b477aa7ab2579c7ea2854a875897a8b8dad0"
-  integrity sha512-t86rLnySRQgN2+58gAIARTEtnClLNZoC99shNrvQ960V/wB9n50AUKJyqly76/s4fT0zwaLFIDFZAW7aK25pvg==
+mini-css-extract-plugin@^1.3.8:
+  version "1.3.8"
+  resolved "https://registry.yarnpkg.com/mini-css-extract-plugin/-/mini-css-extract-plugin-1.3.8.tgz#639047b78c2ee728704285aa468d2a5a8d91d566"
+  integrity sha512-u+2kVov/Gcs74iz+x3phEBWMAGw2djjnKfYez+Pl/b5dyXL7aM4Lp5QQtIq16CDwRHT/woUJki49gBNMhfm1eA==
   dependencies:
     loader-utils "^2.0.0"
     schema-utils "^3.0.0"