Remove novalidate attribute from comment form to enable client-side validation

[rutviksavsani]

Fixes: #364
This PR adds an action to remove the novalidate attribute which is added by WordPress core in the comments form. Removing that attribute will enable client-side validation too for comment form which may not allow invalid data to be submitted.

Screenshot

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[codecov-commenter]

Codecov Report

Merging #717 (2ebebc5) into develop (9935ff9) will decrease coverage by 0.02%.
The diff coverage is 0.00%.

@@              Coverage Diff              @@
##             develop     #717      +/-   ##
=============================================
- Coverage      19.96%   19.93%   -0.03%     
  Complexity       326      326              
=============================================
  Files             56       56              
  Lines           2094     2097       +3     
=============================================
  Hits             418      418              
- Misses          1676     1679       +3     

Flag	Coverage Δ
php	19.93% <0.00%> (-0.03%)	⬇️
unit	19.93% <0.00%> (-0.03%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
pwa.php	0.00% <0.00%> (ø)

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[westonruter]

If offline commenting is removed as suggested in #363 (comment), then this wouldn't be strictly necessary. I'm not totally settled on the direction of that, but I'm leaning towards removal of the feature.

[rutviksavsani]

If offline commenting is removed as suggested in #363 (comment), then this wouldn't be strictly necessary. I'm not totally settled on the direction of that, but I'm leaning towards removal of the feature.

Yes, I also agree with your point for the removal of offline commenting, but until it is completely removed we can add this feature and also remove it along with the offline commenting feature.
We will be deprecating the offline commenting feature at first, hence we can add this as a supporting feature until then.

[westonruter]

We will be deprecating the offline commenting feature at first, hence we can add this as a supporting feature until then.

That's the thing. I think we may just remove it entirely because (1) it's broken when a user tries to comment while logged-in and their nonce expires, and (2) I don't believe anyone is using it (at least I've never heard of someone talking about this feature).

[thelovekesh]

@westonruter Since we are removing the offline-commenting feature in #728, should we close this PR?

[westonruter]

Yes, thanks.