Updated gem dependencies.

Gemfile

@@ -3,4 +3,4 @@
 source "https://rubygems.org"
 
 gem "rake", "~> 12.0"
-gem "git-cop", "~> 1.5"
+gem "git-cop", "~> 1.6"

Gemfile.lock

@@ -2,19 +2,19 @@ GEM
   remote: https://rubygems.org/
   specs:
     equatable (0.5.0)
-    git-cop (1.5.0)
+    git-cop (1.6.0)
       pastel (~> 0.7)
       refinements (~> 4.2)
-      runcom (~> 1.2)
-      thor (~> 0.19)
+      runcom (~> 1.3)
+      thor (~> 0.20)
     pastel (0.7.1)
       equatable (~> 0.5.0)
       tty-color (~> 0.4.0)
     rake (12.0.0)
     refinements (4.2.0)
-    runcom (1.2.0)
+    runcom (1.3.0)
       refinements (~> 4.2)
-    thor (0.19.4)
+    thor (0.20.0)
     tty-color (0.4.2)
 
 PLATFORMS
@@ -25,4 +25,4 @@ DEPENDENCIES
   rake (~> 12.0)
 
 BUNDLED WITH
-   1.15.3
+   1.15.4