workflows/tests: add ruby 3.3 to matrix (#580)

Signed-off-by: William Woodruff <[email protected]>

Author: woodruffw

.github/workflows/tests.yml

@@ -8,7 +8,7 @@ jobs:
     strategy:
       matrix:
         platform: ["ubuntu-latest", "macos-latest"]
-        ruby: [2.6, 2.7, 3.0, 3.1, 3.2]
+        ruby: [2.6, 2.7, 3.0, 3.1, 3.2, 3.3]
     runs-on: ${{ matrix.platform }}
     steps:
     - name: Set up Git repository