Run CI against a Ruby matrix (#1117)

.circleci/config.yml

@@ -1,8 +1,17 @@
-version: 2
+version: 2.1
+
+orbs:
+  # orbs are basically bundles of pre-written build scripts that work for common cases
+  # https://github.com/CircleCI-Public/ruby-orb
+  ruby: circleci/ruby@1.1
+
 jobs:
-  build:
+  test:
+    parameters:
+      ruby-version:
+        type: string
     docker:
-      - image: cimg/ruby:2.7.7-node
+      - image: cimg/ruby:<< parameters.ruby-version >>-node
     steps:
       - checkout
       - restore_cache:
@@ -22,3 +31,12 @@ jobs:
       - run:
           name: Parse SassDoc comments
           command: npm run sassdoc
+workflows:
+  build_and_test:
+    jobs:
+      - test:
+          matrix:
+            parameters:
+              # https://github.com/CircleCI-Public/cimg-ruby
+              # only supports the last three ruby versions
+              ruby-version: ["2.7", "3.0", "3.1", "3.2"]