Bump get-port from 3.2.0 to 4.0.0 (#13)

Bumps [get-port](https://github.com/sindresorhus/get-port) from 3.2.0 to 4.0.0.
- [Release notes](https://github.com/sindresorhus/get-port/releases)
- [Commits](sindresorhus/get-port@v3.2.0...v4.0.0)

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

package.json

@@ -23,7 +23,7 @@
     "eslint-plugin-node": "^6.0.1",
     "eslint-plugin-prettier": "^2.4.0",
     "execa": "^0.10.0",
-    "get-port": "^3.2.0",
+    "get-port": "^4.0.0",
     "prettier": "^1.10.2",
     "qunit": "~2.8.0",
     "qunit-eslint": "^2.0.0",

yarn.lock

@@ -716,9 +716,9 @@ functional-red-black-tree@^1.0.1:
   version "1.0.1"
   resolved "https://registry.yarnpkg.com/functional-red-black-tree/-/functional-red-black-tree-1.0.1.tgz#1b0ab3bd553b2a0d6399d29c0e3ea0b252078327"
 
-get-port@^3.2.0:
-  version "3.2.0"
-  resolved "https://registry.yarnpkg.com/get-port/-/get-port-3.2.0.tgz#dd7ce7de187c06c8bf353796ac71e099f0980ebc"
+get-port@^4.0.0:
+  version "4.0.0"
+  resolved "https://registry.yarnpkg.com/get-port/-/get-port-4.0.0.tgz#373c85960138ee20027c070e3cb08019fea29816"
 
 get-stdin@^5.0.1:
   version "5.0.1"