Update dependency rspec to '~> 3.13.0'

Gemfile

 source 'https://rubygems.org'
 
 group :development, :test do
-  gem 'rspec', '~> 3.12.0'
+  gem 'rspec', '~> 3.13.0'
   gem 'webrick', '~> 1.8', '>= 1.8.1'
 end
 

Gemfile.lock

@@ -28,7 +28,7 @@ GEM
     danger-gitlab (8.0.0)
       danger
       gitlab (~> 4.2, >= 4.2.0)
-    diff-lcs (1.5.0)
+    diff-lcs (1.5.1)
     faraday (2.7.11)
       base64
       faraday-net_http (>= 2.0, < 3.1)
@@ -65,19 +65,19 @@ GEM
     rake (13.1.0)
     rchardet (1.8.0)
     rexml (3.2.6)
-    rspec (3.12.0)
-      rspec-core (~> 3.12.0)
-      rspec-expectations (~> 3.12.0)
-      rspec-mocks (~> 3.12.0)
-    rspec-core (3.12.2)
-      rspec-support (~> 3.12.0)
-    rspec-expectations (3.12.3)
+    rspec (3.13.0)
+      rspec-core (~> 3.13.0)
+      rspec-expectations (~> 3.13.0)
+      rspec-mocks (~> 3.13.0)
+    rspec-core (3.13.0)
+      rspec-support (~> 3.13.0)
+    rspec-expectations (3.13.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.12.0)
-    rspec-mocks (3.12.5)
+      rspec-support (~> 3.13.0)
+    rspec-mocks (3.13.0)
       diff-lcs (>= 1.2.0, < 2.0)
-      rspec-support (~> 3.12.0)
-    rspec-support (3.12.0)
+      rspec-support (~> 3.13.0)
+    rspec-support (3.13.0)
     ruby2_keywords (0.0.5)
     sawyer (0.9.2)
       addressable (>= 2.3.5)
@@ -92,8 +92,8 @@ PLATFORMS
 
 DEPENDENCIES
   gitlab-dangerfiles (~> 4.6.0)
-  rspec (~> 3.12.0)
+  rspec (~> 3.13.0)
   webrick (~> 1.8, >= 1.8.1)
 
 BUNDLED WITH
-   2.4.22
+   2.5.5