Update dependency sass-rails to v6 (#25)

Co-authored-by: Renovate Bot <[email protected]>

Gemfile

@@ -6,7 +6,7 @@ ruby '2.6.3'
 gem 'rails', '~> 5.2.1'
 gem 'mysql2', '>= 0.4.4', '< 0.6.0'
 gem 'puma', '~> 3.12'
-gem 'sass-rails', '~> 5.0'
+gem 'sass-rails', '~> 6.0'
 gem 'uglifier', '>= 1.3.0'
 gem 'turbolinks', '~> 5'
 gem 'bootsnap', '>= 1.1.0', require: false

Gemfile.lock

@@ -89,7 +89,7 @@ GEM
       railties (>= 4.2.0)
     faker (2.11.0)
       i18n (>= 1.6, < 2)
-    ffi (1.14.2)
+    ffi (1.15.0)
     font_awesome5_rails (1.1.1)
       railties (>= 4.2)
     globalid (0.4.2)
@@ -168,7 +168,7 @@ GEM
       rake (>= 0.8.7)
       thor (>= 0.19.0, < 2.0)
     rake (13.0.3)
-    rb-fsevent (0.10.3)
+    rb-fsevent (0.10.4)
     rb-inotify (0.10.1)
       ffi (~> 1.0)
     responders (3.0.0)
@@ -194,17 +194,8 @@ GEM
     ruby-vips (2.0.17)
       ffi (~> 1.9)
     ruby_dep (1.5.0)
-    sass (3.7.4)
-      sass-listen (~> 4.0.0)
-    sass-listen (4.0.0)
-      rb-fsevent (~> 0.9, >= 0.9.4)
-      rb-inotify (~> 0.9, >= 0.9.7)
-    sass-rails (5.1.0)
-      railties (>= 5.2.0)
-      sass (~> 3.1)
-      sprockets (>= 2.8, < 4.0)
-      sprockets-rails (>= 2.0, < 4.0)
-      tilt (>= 1.1, < 3)
+    sass-rails (6.0.0)
+      sassc-rails (~> 2.1, >= 2.1.1)
     sassc (2.4.0)
       ffi (~> 1.9)
     sassc-rails (2.1.2)
@@ -234,7 +225,7 @@ GEM
     spring-watcher-listen (2.0.1)
       listen (>= 2.7, < 4.0)
       spring (>= 1.2, < 3.0)
-    sprockets (3.7.2)
+    sprockets (4.0.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
     sprockets-rails (3.2.2)
@@ -285,7 +276,7 @@ DEPENDENCIES
   rails (~> 5.2.1)
   rails-controller-testing
   rspec-rails (~> 4.0.2)
-  sass-rails (~> 5.0)
+  sass-rails (~> 6.0)
   shoulda (~> 3.5)
   shoulda-matchers
   simplecov