not so many builds please

.github/workflows/tests.yml

@@ -1,4 +1,3 @@
-
 name: Squib Unit Tests
 
 on: [push]
@@ -9,7 +8,7 @@ jobs:
       fail-fast: false
       matrix:
         os: [ubuntu, macos]
-        ruby: [2.5, 2.6, 2.7, head, debug, jruby, jruby-head, truffleruby, truffleruby-head]
+        ruby: [2.5, 2.6, 2.7, head]
     runs-on: ${{ matrix.os }}-latest
     continue-on-error: ${{ endsWith(matrix.ruby, 'head') || matrix.ruby == 'debug' }}
     steps:
@@ -18,5 +17,6 @@ jobs:
       with:
         ruby-version: ${{ matrix.ruby }}
         # bundler-cache: true # runs 'bundle install' and caches installed gems automatically
+    - run: ruby --version # explicitly show the ruby version
     - run: bundle install
     - run: bundle exec rake