Update hexo-util requirement from ^0.6.0 to ^1.0.0

Updates the requirements on [hexo-util](https://github.com/hexojs/hexo-util) to permit the latest version.
- [Release notes](https://github.com/hexojs/hexo-util/releases)
- [Commits](hexojs/hexo-util@0.6.0...1.0.0)

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

package.json

@@ -39,7 +39,7 @@
     "bluebird": "^3.5.0",
     "chalk": "^2.4.1",
     "hexo-fs": "^1.0.0",
-    "hexo-util": "^0.6.0",
+    "hexo-util": "^1.0.0",
     "moment": "^2.18.0",
     "swig-templates": "^2.0.2"
   },