Bump typescript from 3.9.7 to 4.0.3 (#291)

Bumps [typescript](https://github.com/Microsoft/TypeScript) from 3.9.7 to 4.0.3.
- [Release notes](https://github.com/Microsoft/TypeScript/releases)
- [Commits](microsoft/TypeScript@v3.9.7...v4.0.3)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

Co-authored-by: dependabot-preview[bot] <27856297+dependabot-preview[bot]@users.noreply.github.com>

package.json

@@ -54,7 +54,7 @@
     "mockjs": "^1.1.0",
     "prettier": "^2.0.2",
     "stylelint": "^13.0.0",
-    "typescript": "^3.5.1"
+    "typescript": "^4.0.3"
   },
   "checkFiles": [
     "**/*.ts*",