DX-1846: Use Ruby version 2.7.6

Author: asbjornu

.docker/entrypoint/.rubocop.yml

@@ -8,7 +8,7 @@ AllCops:
     - _site/**/*
     - spec/**/*
     - vendor/**/*
-  TargetRubyVersion: 2.7
+  TargetRubyVersion: 2.7.6
 Layout:
   LineLength: 100
   IndentationStyle:

.github/workflows/test.yml

@@ -178,7 +178,7 @@ jobs:
       - uses: actions/checkout@v3
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.7
+          ruby-version: 2.7.6
           bundler-cache: true
           working-directory: ${{ env.working-directory }}
       - run: bundle exec rake
@@ -195,7 +195,7 @@ jobs:
 
       - uses: ruby/setup-ruby@v1
         with:
-          ruby-version: 2.7
+          ruby-version: 2.7.6
           bundler-cache: true
 
       - name: Verify build output