Update core-js to optimize speed.

[rokyed]

Hi, I get core-js being outdate and possibly causing slowness. Here's all the info I have so far:

npm run node list
...
├─┬ @paperbits/firebase@0.1.543
│ └─┬ firebase@7.24.0
│   └─┬ @firebase/polyfill@0.3.36
│     └── core-js@3.6.5 # this is an old version and should be 
...

The note i get durring CI install:

npm WARN deprecated core-js@3.6.5: core-js@<3.23.3 is no longer maintained and not recommended for usage due to the number of issues.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. Some versions have web compatibility issues. Please, upgrade your dependencies to the actual version of core-js.

I suggest to upgrade firebase at the current stable release 9.15.0 https://www.npmjs.com/package/firebase/v/9.15.0

Thank you very much!