CI against rails 7.0

and kick out ruby 2.6 from the matrix since rails 7 doesn't support ruby 2.6

.github/workflows/ruby.yml

@@ -21,13 +21,13 @@ jobs:
       matrix:
         ruby-version:
           - jruby-9.2.9.0
-          - 2.6
           - 2.7
           - 3.0
           - 3.1
         gemfile:
           - rails_6_0
           - rails_6_1
+          - rails_7_0
 
         include:
           - ruby-version: 2.7
@@ -35,6 +35,10 @@ jobs:
           - ruby-version: 2.7
             gemfile: rails_5_1
 
+          - ruby-version: 2.6
+            gemfile: rails_6_1
+          - ruby-version: 2.6
+            gemfile: rails_6_0
           - ruby-version: 2.6
             gemfile: rails_5_2
           - ruby-version: 2.6

Appraisals

@@ -13,3 +13,7 @@ end
 appraise "rails_6_1" do
   gem "rails", "~> 6.1.0"
 end
+
+appraise "rails_7_0" do
+  gem "rails", "~> 7.0.0"
+end

gemfiles/rails_7_0.gemfile

@@ -0,0 +1,8 @@
+# This file was generated by Appraisal
+
+source "https://rubygems.org"
+
+gem "html2haml"
+gem "rails", "~> 7.0.0"
+
+gemspec path: "../"