add latest rails and reduced matrix

Left rails 5.0, 5.1, 6.0 in there even though both the ruby and rails for them are EOL
Not sure the versions the users of this gem are using

Rails 6.1 (suggested ruby 3.0.x) and 7.0 are the only current rails versions

Held off on rails 7.0
will leave this effort to another PR

.github/workflows/ruby.yml

@@ -7,17 +7,26 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        ruby: ['2.4', '2.5', '2.6', '2.7', '3.0']
-        gemfile: ['gemfiles/rails_5.0.gemfile', 'gemfiles/rails_5.1.gemfile', 'gemfiles/rails_5.2.gemfile', 'gemfiles/rails_6.0.gemfile']
-        exclude:
-          - ruby: '2.4'
-            gemfile: 'gemfiles/rails_6.0.gemfile'
-          - ruby: '3.0'
-            gemfile: 'gemfiles/rails_5.0.gemfile'
-          - ruby: '3.0'
-            gemfile: 'gemfiles/rails_5.1.gemfile'
-          - ruby: '3.0'
-            gemfile: 'gemfiles/rails_5.2.gemfile'
+        # | rails | rails EOL | ruby EOL | min ruby| max |
+        # | ----- | ---------+| --------+| --------|---- |
+        # | 5.0   |  6/2020   |   3/2020 |   2.2   | 2.4 |
+        # | 5.1   |  6/2021   |   3/2021 |   2.2   | 2.5 |
+        # | 5.2   |  6/2022   |   3/2022 |   2.2   | 2.6 |
+        # | 6.0   |  6/2023?  |   3/3023?|   2.5   | 2.7 |
+        # | 6.1   |           |          |   2.5   |     |
+        # | 7.0   |           |          |   2.7   |     |
+        ruby: ['3.0', '3.1']
+        gemfile: ['gemfiles/rails_6.1.gemfile']
+          #   gemfile: 'gemfiles/rails_7.0.gemfile'
+        include:
+        - ruby: '2.4'
+          gemfile: 'gemfiles/rails_5.0.gemfile'
+        - ruby: '2.5'
+          gemfile: 'gemfiles/rails_5.1.gemfile'
+        - ruby: '2.6'
+          gemfile: 'gemfiles/rails_5.2.gemfile'
+        - ruby: '2.7'
+          gemfile: 'gemfiles/rails_6.0.gemfile'
     env:
       BUNDLE_GEMFILE: ${{ matrix.gemfile }}
     name: Ruby ${{ matrix.ruby }}, ${{ matrix.gemfile }}

gemfiles/rails_6.1.gemfile

@@ -0,0 +1,18 @@
+source 'http://rubygems.org/'
+
+gem 'activerecord', '~> 6.1.0'
+gem 'rspec', '~> 3.9'
+gem 'wwtd'
+gem 'rake', '~> 13.0'
+gem 'json'
+gem 'test-unit'
+
+platform :jruby do
+  gem 'activerecord-jdbcsqlite3-adapter', '>= 1.3.6'
+end
+
+platform :ruby do
+  gem 'sqlite3'
+end
+
+gemspec :path => '../'

gemfiles/rails_7.0.gemfile

@@ -0,0 +1,18 @@
+source 'http://rubygems.org/'
+
+gem 'activerecord', '~> 7.0.0'
+gem 'rspec', '~> 3.9'
+gem 'wwtd'
+gem 'rake', '~> 13.0'
+gem 'json'
+gem 'test-unit'
+
+platform :jruby do
+  gem 'activerecord-jdbcsqlite3-adapter', '>= 1.3.6'
+end
+
+platform :ruby do
+  gem 'sqlite3'
+end
+
+gemspec :path => '../'