Bump sinon from 7.5.0 to 9.1.0

Bumps [sinon](https://github.com/sinonjs/sinon) from 7.5.0 to 9.1.0.
- [Release notes](https://github.com/sinonjs/sinon/releases)
- [Changelog](https://github.com/sinonjs/sinon/blob/master/CHANGELOG.md)
- [Commits](sinonjs/sinon@v7.5.0...v9.1.0)

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

package.json

@@ -31,7 +31,7 @@
         "grunt-jsbeautifier" : "^0.2.13",
         "istanbul" : "^0.4.5",
         "mocha" : "^6.2.1",
-        "sinon" : "^7.5.0",
+        "sinon" : "^9.1.0",
         "sinon-chai" : "^3.3.0"
     }
 }