update ci build; bump rake gem

Author: Chris Bloom

.github/workflows/ruby.yml

@@ -24,10 +24,7 @@ jobs:
     steps:
     - uses: actions/checkout@v2
     - name: Set up Ruby
-    # To automatically get bug fixes and new Ruby versions for ruby/setup-ruby,
-    # change this to (see https://github.com/ruby/setup-ruby#versioning):
-    # uses: ruby/setup-ruby@v1
-      uses: ruby/setup-ruby@473e4d8fe5dd94ee328fdfca9f8c9c7afc9dae5e
+      uses: ruby/setup-ruby@v1
       with:
         ruby-version: ${{ matrix.ruby-version }}
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically

Gemfile.lock

@@ -23,7 +23,7 @@ GEM
     pry-byebug (3.9.0)
       byebug (~> 11.0)
       pry (~> 0.13.0)
-    rake (13.0.3)
+    rake (13.0.6)
     redcarpet (3.5.1)
     rspec (3.10.0)
       rspec-core (~> 3.10.0)