Update glob dependency

[denysvitali]

mocha still depends on glob@3.2.3 when the version 7.0.3 is out
Having mocha to depend on glob@3.2.3 means that graceful-fs is still at version 2.0.3, so the following warning is shown:
npm WARN deprecated graceful-fs@2.0.3: graceful-fs version 3 and before will fail on newer node releases. Please update to graceful-fs@^4.0.0 as soon as possible.

[danielstjules]

Thanks! Closing as duplicate of #2121