ruby 2.4 compat: update to webmock 2.3.2

Gemfile

@@ -354,7 +354,7 @@ group :test do
   gem 'shoulda-matchers', '~> 2.8.0', require: false
   gem 'email_spec', '~> 1.6.0'
   gem 'json-schema', '~> 2.6.2'
-  gem 'webmock', '~> 1.24.0'
+  gem 'webmock', '~> 2.3.2'
   gem 'test_after_commit', '~> 1.1'
   gem 'sham_rack', '~> 1.3.6'
   gem 'timecop', '~> 0.8.0'

Gemfile.lock

@@ -366,7 +366,7 @@ GEM
       temple (~> 0.7.6)
       thor
       tilt
-    hashdiff (0.3.2)
+    hashdiff (0.3.4)
     hashie (3.5.5)
     hashie-forbidden_attributes (0.1.1)
       hashie (>= 3.0)
@@ -888,7 +888,7 @@ GEM
     vmstat (2.3.0)
     warden (1.2.6)
       rack (>= 1.0)
-    webmock (1.24.6)
+    webmock (2.3.2)
       addressable (>= 2.3.6)
       crack (>= 0.3.2)
       hashdiff
@@ -1118,7 +1118,7 @@ DEPENDENCIES
   version_sorter (~> 2.1.0)
   virtus (~> 1.0.1)
   vmstat (~> 2.3.0)
-  webmock (~> 1.24.0)
+  webmock (~> 2.3.2)
   webpack-rails (~> 0.9.10)
   wikicloth (= 0.8.1)