chore(deps-dev): bump typescript from 3.4.2 to 3.4.3

Bumps [typescript](https://github.com/Microsoft/TypeScript) from 3.4.2 to 3.4.3.
- [Release notes](https://github.com/Microsoft/TypeScript/releases)
- [Commits](https://github.com/Microsoft/TypeScript/commits)

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

yarn.lock

@@ -6815,9 +6815,9 @@ typedarray@^0.0.6:
   integrity sha1-hnrHTjhkGHsdPUfZlqeOxciDB3c=
 
 typescript@^3.0.0-rc:
-  version "3.4.2"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.4.2.tgz#9ed4e6475d906f589200193be056f5913caed481"
-  integrity sha512-Og2Vn6Mk7JAuWA1hQdDQN/Ekm/SchX80VzLhjKN9ETYrIepBFAd8PkOdOTK2nKt0FCkmMZKBJvQ1dV1gIxPu/A==
+  version "3.4.3"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-3.4.3.tgz#0eb320e4ace9b10eadf5bc6103286b0f8b7c224f"
+  integrity sha512-FFgHdPt4T/duxx6Ndf7hwgMZZjZpB+U0nMNGVCYPq0rEzWKjEDobm4J6yb3CS7naZ0yURFqdw9Gwc7UOh/P9oQ==
 
 uglify-js@^2.4.19, uglify-js@^2.6.1:
   version "2.8.29"