CI: Disable benchmarking of some versions on Ruby

Author: mrkn

.github/workflows/benchmark.yml

@@ -37,6 +37,11 @@ jobs:
         exclude:
         - { os: windows-latest , ruby: debug }
 
+        # These are disabled due to the ambiguity of stringio
+        - { os: windows-latest , ruby: "3.0" }
+        - { os: windows-latest , ruby: "3.1" }
+        - { os: windows-latest , ruby: "3.2" }
+
     steps:
     - uses: actions/checkout@v4