fix: Gemfile & Gemfile.lock to reduce vulnerabilities

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-RUBY-RACK-1061917

Gemfile

@@ -112,7 +112,7 @@ gem "exception_notification"
 gem "zipline"
 gem "rack-headers_filter"
 gem "strip_attributes"
-gem "omniauth"
+gem "omniauth", ">= 2.1.2"
 gem "omniauth-google-oauth2"
 gem "omniauth-rails_csrf_protection"
 gem "omniauth-azure-activedirectory", git: "https://github.com/murb/omniauth-azure-activedirectory.git"

Gemfile.lock

@@ -336,7 +336,7 @@ GEM
       rack (>= 1.2, < 4)
       snaky_hash (~> 2.0)
       version_gem (~> 1.1)
-    omniauth (2.1.1)
+    omniauth (2.1.2)
       hashie (>= 3.4.6)
       rack (>= 2.2.3)
       rack-protection
@@ -633,7 +633,7 @@ DEPENDENCIES
   mini_magick
   nested_form
   nokogiri
-  omniauth
+  omniauth (>= 2.1.2)
   omniauth-azure-activedirectory!
   omniauth-central_login!
   omniauth-google-oauth2