Use Loofah 2.2.3 to address CVE-2018-16468

[kaspergrubbe]

More info at flavorjones/loofah#154

[rails-bot]

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[matthewd]

Thanks, but we prefer not to bump our dependencies just to force upgrades of other libraries. This change is not needed for applications to begin using the new updated version.

[kaspergrubbe]

Ok, I was following the example of @rafaelfranca here: f3ba1a8#diff-92136a8a78ef91cb482af8640395756dR20

Sorry for wasting your time.

[matthewd]

No worries! That was a special case because we needed the new loofah plus our own change in order to fully address the issue.