fix: package.json & yarn.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-JS-SERIALIZEJAVASCRIPT-6147607

package.json

@@ -48,7 +48,7 @@
     "classnames": "^2.3.2",
     "cocoon-js-vanilla": "^1.3.0",
     "color-blend": "^3.0.1",
-    "compression-webpack-plugin": "^6.1.1",
+    "compression-webpack-plugin": "^8.0.1",
     "cross-env": "^7.0.3",
     "css-loader": "^5.2.7",
     "cssnano": "^4.1.11",
@@ -123,13 +123,13 @@
     "stacktrace-js": "^2.0.2",
     "stringz": "^2.1.0",
     "substring-trie": "^1.0.2",
-    "terser-webpack-plugin": "^4.2.3",
+    "terser-webpack-plugin": "^5.1.4",
     "tesseract.js": "^2.1.1",
     "throng": "^4.0.0",
     "tiny-queue": "^0.2.1",
     "twitter-text": "3.1.0",
     "uuid": "^8.3.1",
-    "webpack": "^4.46.0",
+    "webpack": "^5.1.1",
     "webpack-assets-manifest": "^4.0.6",
     "webpack-bundle-analyzer": "^4.6.1",
     "webpack-cli": "^3.3.12",