Merge branch 'sh-bump-parser-gem' into 'master'

Bump parser gem to 2.5.1.0 to remove warning in rspec

See merge request gitlab-org/gitlab-ce!18384

Gemfile.lock

@@ -590,7 +590,7 @@ GEM
     orm_adapter (0.5.0)
     os (0.9.6)
     parallel (1.12.1)
-    parser (2.5.0.5)
+    parser (2.5.1.0)
       ast (~> 2.4.0)
     parslet (1.5.0)
       blankslate (~> 2.0)