chore(deps): update devdependency standard-version to v8 [security]

Author: renovate[bot]

Diff for: package.json

@@ -78,7 +78,7 @@
     "jest": "^24.5.0",
     "jest-serializer-vue": "^2.0.2",
     "jsdom": "^14.0.0",
-    "standard-version": "^5.0.1",
+    "standard-version": "^8.0.0",
     "vue-jest": "^3.0.4",
     "vue-router": "^3.0.2",
     "vue-server-renderer": "^2.6.9",