Revert "[CI] Test JRuby 10.0"

This reverts commit 9bde3c3.

Author: picandocodigo

.buildkite/pipeline.yml

@@ -14,7 +14,7 @@ steps:
           - "8.4"
       adjustments:
         - with: # JRuby tests
-            ruby: "10.0"
+            ruby: "9.4"
             ruby_source: "jruby"
             transport: "8.4"
         # Test for different versions of transport

.github/workflows/main.yml

@@ -14,7 +14,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby: ['head', '3.2', '3.3', '3.4', 'jruby-9.4', 'jruby-10.0']
+        ruby: ['head', '3.2', '3.3', '3.4', 'jruby-9.3', 'jruby-9.4', 'jruby-head']
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v4