Feature/jquery 3 5 0 compatibility

[tagliala]

Quoting from https://blog.jquery.com/2020/04/10/jquery-3-5-0-released/

Security Fix

The main change in this release is a security fix, and it’s possible you will need to change your own code to adapt. Here’s why: jQuery used a regex in its jQuery.htmlPrefilter method to ensure that all closing tags were XHTML-compliant when passed to methods. For example, this prefilter ensured that a call like jQuery("<div class='hot' />") is actually converted to jQuery("<div class='hot'></div>"). Recently, an issue was reported that demonstrated the regex could introduce a cross-site scripting (XSS) vulnerability.

The HTML parser in jQuery <=3.4.1 usually did the right thing, but there were edge cases where parsing would have unintended consequences. The jQuery team agreed it was necessary to fix this in a minor release, even though some code relies on the previous behavior and may break. The jQuery.htmlPrefilter function does not use a regex in 3.5.0 and passes the string through unchanged.

This PR:

• Tests against jQuery 3.5.0
• Fixes JS tests
• Fixes Ruby tests
• Changes the default input_tag and label_tag to XHTML-compliant tags

[coveralls]

Coverage remained the same at 100.0% when pulling 8a3600e on feature/jquery-3_5_0-compatibility into ef3126c on master.