Update dependency typescript to v4

Author: renovate-bot

package.json

@@ -105,7 +105,7 @@
     "nyc": "^14.1.1",
     "sinon": "^7.5.0",
     "supertest": "^4.0.2",
-    "typescript": "^3.7.2",
+    "typescript": "^4.0.0",
     "webmention-testpinger": "^0.7.0"
   }
 }

yarn.lock

@@ -5626,10 +5626,10 @@ typedarray@^0.0.6:
   resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
   integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
 
-typescript@^3.7.2:
-  version "3.7.2"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.7.2.tgz#27e489b95fa5909445e9fef5ee48d81697ad18fb"
-  integrity sha512-ml7V7JfiN2Xwvcer+XAf2csGO1bPBdRbFCkYBczNZggrBZ9c7G3riSUeJmqEU5uOtXNPMhE3n+R4FA/3YOAWOQ==
+typescript@^4.0.0:
+  version "4.4.4"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-4.4.4.tgz#2cd01a1a1f160704d3101fd5a58ff0f9fcb8030c"
+  integrity sha512-DqGhF5IKoBl8WNf8C1gu8q0xZSInh9j1kJJMqT3a94w1JzVaBU4EXOSMrz9yDqMT0xt3selp83fuFMQ0uzv6qA==
 
 uglify-js@^3.1.4:
   version "3.6.8"