add border-hidden

[kwaa]

implementing #1558, add border-hidden in borderStyle.js.

'.border-hidden': {
  'border-style': 'hidden',
},

MDN

[codecov-io]

Codecov Report

Merging #3806 (e81e0ec) into master (e227320) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #3806   +/-   ##
=======================================
  Coverage   93.34%   93.34%           
=======================================
  Files         178      178           
  Lines        1849     1849           
  Branches      332      332           
=======================================
  Hits         1726     1726           
  Misses        105      105           
  Partials       18       18           

Impacted Files	Coverage Δ
src/plugins/borderStyle.js	100.00% <ø> (ø)

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[samarmohan]

fix the conflicts first

[Raj-k-Jha]

'.border-hidden': {
'border-style': 'hidden',
},

[adamwathan]

Reworked this here due to merge conflicts, but added as co-author so still get credit 👍🏻

#5485

Thanks!