Simplify VALID_TAG_NAMES definition

[chrissantamaria]

Hi all 👋 this is a small one, just cleans up the definition of the VALID_TAG_NAMES array. Not sure if there's a reason to use Object.keys if the goal is to get an array of values anyways.

[codecov]

Codecov Report

Merging #603 into master will decrease coverage by 0.01%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master     #603      +/-   ##
==========================================
- Coverage   96.91%   96.90%   -0.02%     
==========================================
  Files           3        3              
  Lines         292      291       -1     
==========================================
- Hits          283      282       -1     
  Misses          9        9              

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

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[cwelch5]

Thanks, that's a good call.

[realityking]

I don't have a problem with this but note that Object.values requires either somewhat recent browser (e.g. no IE11) or a polyfill. Source: https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_objects/Object/values

I think that's fine since most folks already use something like core-js but it should be documented. It also means the dependency on object-assign could be dropped since every browser that supports Object.values will also support Object.assign.