Bump omniauth from 1.7.1 to 1.8.1

Bumps [omniauth](https://github.com/omniauth/omniauth) from 1.7.1 to 1.8.1.
- [Release notes](https://github.com/omniauth/omniauth/releases)
- [Commits](omniauth/omniauth@v1.7.1...v1.8.1)

Author: dependabot-support

Gemfile

@@ -19,7 +19,7 @@ gem 'pg', '~> 0.18.2'
 gem 'activerecord-postgresql-adapter'
 
 gem 'devise', '~> 3.5.5'
-gem 'omniauth', '~> 1.7.1' # 1.2.2 breaks test sign_in
+gem 'omniauth', '~> 1.8.1' # 1.2.2 breaks test sign_in
 gem 'omniauth-shibboleth', '~> 1.2.1'
 gem 'equivalent-xml', '~> 0.6.0'
 

Gemfile.lock

@@ -155,7 +155,7 @@ GEM
     ffi (1.9.10)
     globalid (0.3.7)
       activesupport (>= 4.1.0)
-    hashie (3.5.6)
+    hashie (3.5.7)
     hike (1.2.3)
     hooks (0.3.6)
       uber (~> 0.0.4)
@@ -240,7 +240,7 @@ GEM
       mediashelf-loggable
       nokogiri (>= 1.4.2)
       solrizer (~> 3.1.0)
-    omniauth (1.7.1)
+    omniauth (1.8.1)
       hashie (>= 3.4.6, < 3.6.0)
       rack (>= 1.6.2, < 3)
     omniauth-shibboleth (1.2.1)
@@ -268,7 +268,7 @@ GEM
       nokogiri (~> 1.6)
       rails (>= 4.2.0, < 6.0)
       rdf
-    rack (1.6.8)
+    rack (1.6.10)
     rack-dev-mark (0.7.5)
       rack (>= 1.1)
     rack-test (0.6.3)
@@ -460,7 +460,7 @@ DEPENDENCIES
   minitest (~> 5.10.2)
   newrelic_rpm (= 5.3.0.346)
   nokogiri (= 1.8.4)
-  omniauth (~> 1.7.1)
+  omniauth (~> 1.8.1)
   omniauth-shibboleth (~> 1.2.1)
   pg (~> 0.18.2)
   poltergeist (= 1.15.0)