chore(deps-dev): bump standard-version from 4.0.0 to 7.1.0

Bumps [standard-version](https://github.com/conventional-changelog/standard-version) from 4.0.0 to 7.1.0.
- [Release notes](https://github.com/conventional-changelog/standard-version/releases)
- [Changelog](https://github.com/conventional-changelog/standard-version/blob/master/CHANGELOG.md)
- [Commits](conventional-changelog/standard-version@v4.0.0...v7.1.0)

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

package.json

@@ -33,7 +33,7 @@
     "istanbul": "^0.4.5",
     "mocha": "^3.2.0",
     "should": "^11.1.2",
-    "standard-version": "^4.0.0"
+    "standard-version": "^7.1.0"
   },
   "scripts": {
     "test": "mocha",