update dependencies

package.json

@@ -11,8 +11,8 @@
   },
   "dependencies": {
     "balloon-css": "^1.0.4",
-    "highlight.js": "^9.10.0",
-    "markdown-it": "^10.0.0",
+    "highlight.js": "^10.1.1",
+    "markdown-it": "^11.0.0",
     "mathjax-node-page": "^3.0.1",
     "mathjax3": "^3.0.0-beta.2",
     "milligram": "git+https://github.com/Findus23/milligram.git#0fde381605c1159f39efb5c33c9600331fec4e2e",
@@ -31,14 +31,14 @@
     "babel-loader": "^8.0.0-beta.0",
     "blurhash": "^1.1.3",
     "clean-webpack-plugin": "^3.0.0",
-    "compression-webpack-plugin": "^3.0.0",
+    "compression-webpack-plugin": "^4.0.0",
     "cross-env": "^7.0.0",
     "css-loader": "^3.0.0",
-    "eslint": "^6.0.1",
-    "eslint-loader": "^3.0.2",
+    "eslint": "^7.4.0",
+    "eslint-loader": "^4.0.2",
     "eslint-plugin-html": "^6.0.0",
-    "file-loader": "^5.1.0",
-    "html-webpack-plugin": "3.2.0",
+    "file-loader": "^6.0.0",
+    "html-webpack-plugin": "4.3.0",
     "image-webpack-loader": "^6.0.0",
     "js-yaml": "^3.12.0",
     "license-webpack-plugin": "^2.0.0-alpha.7",
@@ -46,8 +46,8 @@
     "node-sass": "^4.7.2",
     "postcss-loader": "3",
     "prerender-spa-plugin": "^3.0.0-beta.2",
-    "sass-loader": "^8.0.0",
-    "sharp": "^0.24.0",
+    "sass-loader": "^9.0.2",
+    "sharp": "^0.25.4",
     "vue-loader": "^15.2.4",
     "vue-template-compiler": "^2.5.13",
     "webpack": "^4.12.0",