Test on JRuby 10.1, ruby-head, and jruby-head

JRuby 10.1 targets Ruby 4.0, a language level JRuby 10.0 does not
cover, so it joins the matrix alongside 10.0.

ruby-head and jruby-head show breakage from upcoming releases early.
They are allowed to fail, so a regression upstream does not turn the
build red.

Author: sferik

.github/workflows/benchmark.yml

@@ -15,7 +15,7 @@ jobs:
     strategy:
       fail-fast: false
       matrix:
-        ruby-version: ["4.0", "jruby-10.0", "truffleruby"]
+        ruby-version: ["4.0", "jruby-10.0", "jruby-10.1", "truffleruby"]
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v7

.github/workflows/tests.yml

@@ -15,14 +15,15 @@ jobs:
   test:
     strategy:
       matrix:
-        ruby-version: ['3.2', '3.3', '3.4', '4.0', 'jruby-10.0', 'truffleruby', 'truffleruby+graalvm']
+        ruby-version: ['3.2', '3.3', '3.4', '4.0', 'jruby-10.0', 'jruby-10.1', 'ruby-head', 'jruby-head', 'truffleruby', 'truffleruby+graalvm']
         platform: [ubuntu-latest, macos-latest, windows-latest]
         exclude:
           - ruby-version: truffleruby
             platform: windows-latest
           - ruby-version: truffleruby+graalvm
             platform: windows-latest
     runs-on: ${{ matrix.platform }}
+    continue-on-error: ${{ endsWith(matrix.ruby-version, '-head') }}
 
     steps:
     - uses: actions/checkout@v7