Fix base64url security alert

package.json

@@ -89,5 +89,8 @@
     "webpack-cli": "^3.3.10",
     "webpack-dev-server": "^3.9.0",
     "webpack-merge": "^4.2.2"
+  },
+  "resolutions": {
+    "base64url": "^3.0.0"
   }
 }

yarn.lock

@@ -3010,9 +3010,10 @@ base64-js@^1.0.2:
   version "1.2.1"
   resolved "https://registry.yarnpkg.com/base64-js/-/base64-js-1.2.1.tgz#a91947da1f4a516ea38e5b4ec0ec3773675e0886"
 
-base64url@2.0.0, base64url@^2.0.0:
-  version "2.0.0"
-  resolved "https://registry.yarnpkg.com/base64url/-/base64url-2.0.0.tgz#eac16e03ea1438eff9423d69baa36262ed1f70bb"
+base64url@2.0.0, base64url@^2.0.0, base64url@^3.0.0:
+  version "3.0.1"
+  resolved "https://registry.yarnpkg.com/base64url/-/base64url-3.0.1.tgz#6399d572e2bc3f90a9a8b22d5dbb0a32d33f788d"
+  integrity sha512-ir1UPr3dkwexU7FdV8qBBbNDRUhMmIekYMFZfi+C/sLNnRESKPl23nB9b2pltqfOQNnGzsDdId90AEtG5tCx4A==
 
 base@^0.11.1:
   version "0.11.2"