⬆️💚 update gulp to v4, fix build issues

[radibit]

Hey there!

Thanks for contributing to perf-tooling!

Please make sure that you followed the following conventions:

• [x] your commits follow the gitmoji convention
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Description

The following PR addresses the following issue which started since build 1477 and it's related to an incompatibility of gulp v3 and the required Node.js version.