babel-polyfill in package dependencies??

[szegheo]

Hi!

I've just noticed that with cockpit-sdk npm generates the following warning:

 WARN  deprecated core-js@2.6.12: core-js@<3.3 is no longer maintained and not recommended for usage due to the number of issues. Because of the V8 engine whims, feature detection in old core-js versions could cause a slowdown up to 100x even if nothing is polyfilled. Please, upgrade your dependencies to the actual version of core-js.

dependency tree:

cockpit-sdk 0.15.1
└─┬ babel-polyfill 6.26.0
  ├─┬ babel-runtime 6.26.0
  │ └── core-js 2.6.12
  └── core-js 2.6.12

The deprecated warning is one thing, but more important is that it seems babel-polyfill is used only in the examples - and maybe is required for the npm build script -, so if I'm not mistaken, babel-polyfill should be moved to devDependencies. (or removed?)