fix(core): add enterKeyHint to list of htmlInputAttrs

[ben-rogerson]

This PR adds the missing enterKeyHint attribute which allows the customisability of the enter key on virtual keyboards.

In my usage, this fixes an issue on Android where the enter button character doesn't reflect the action it performs.

Closes #4371

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[codecov-commenter]

Codecov Report

Merging #4377 (22037cf) into master (134ba34) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4377   +/-   ##
=======================================
  Coverage   99.75%   99.75%           
=======================================
  Files         180      180           
  Lines        3248     3248           
=======================================
  Hits         3240     3240           
  Misses          8        8           

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