Merge pull request rsim#2401 from yahonda/enable_safe_navigation_chain_cop

Enable `Lint/SafeNavigationChain` cop

Author: yahonda

.rubocop.yml

@@ -74,6 +74,9 @@ Layout/EmptyLinesAroundMethodBody:
 Layout/EmptyLinesAroundModuleBody:
   Enabled: true
 
+Lint/SafeNavigationChain:
+  Enabled: true
+
 # Use Ruby >= 1.9 syntax for hashes. Prefer { a: :b } over { :a => :b }.
 Style/HashSyntax:
   Enabled: true