[Security] Bump loofah from 2.1.1 to 2.2.2

Bumps [loofah](https://github.com/flavorjones/loofah) from 2.1.1 to 2.2.2. **This update includes security fixes.**
- [Release notes](https://github.com/flavorjones/loofah/releases)
- [Changelog](https://github.com/flavorjones/loofah/blob/master/CHANGELOG.md)
- [Commits](flavorjones/loofah@v2.1.1...v2.2.2)

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -71,7 +71,7 @@ GEM
     coderay (1.1.2)
     concurrent-ruby (1.0.5)
     connection_pool (2.2.1)
-    crass (1.0.3)
+    crass (1.0.4)
     database_cleaner (1.6.2)
     diff-lcs (1.3)
     dotenv (2.2.1)
@@ -112,7 +112,7 @@ GEM
       activesupport (>= 4.0)
       logstash-event (~> 1.2.0)
       request_store
-    loofah (2.1.1)
+    loofah (2.2.2)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.0)
@@ -125,7 +125,7 @@ GEM
     mustermann (1.0.1)
     newrelic_rpm (4.7.1.340)
     nio4r (2.2.0)
-    nokogiri (1.8.1)
+    nokogiri (1.8.3)
       mini_portile2 (~> 2.3.0)
     panoptes-client (0.3.5)
       faraday