chore(package): correct peer dependencies

[layershifter]

Fixes #440.

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I've made 16.3 as minimal required because:

• we will want to use forwardRef() API (Create and initialise default ref prop for Startdust components #417) that was introduced in 16.3
• we're using createRef() from 16.3
• we're widely using Fragment API from 16.2 in components

[codecov]

Codecov Report

Merging #452 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master     #452   +/-   ##
=======================================
  Coverage   88.96%   88.96%           
=======================================
  Files          41       41           
  Lines        1386     1386           
  Branches      177      177           
=======================================
  Hits         1233     1233           
  Misses        149      149           
  Partials        4        4

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