Core: Allow string in object arg and support fractional numbers in URL args

[ghengeveld]

Issue: #14508

What I did

• Add support for fractional numbers in URL args
• Allow raw strings and numbers when parsing object arg param (e.g. for ReactNode)

How to test

• Is this testable with Jest or Chromatic screenshots? no
• Does this need a new example in the kitchen sink apps? no
• Does this need an update to the documentation? no

If your answer is yes to any of these, please make sure to include it in your PR.

[shilman]

LGTM!