ci(e2e_gem): bump pinned ruby from 3.2.11 to 3.2.10

`ruby/setup-ruby` dropped 3.2.11 from its catalog at some point —
the action errors with "Unknown version 3.2.11 for ruby on
ubuntu-24.04" and lists 3.2.10 as the newest 3.2.x available.

3.2.x is API-stable so 3.2.10 is a drop-in replacement.

Assisted-by: Claude Code:opus-4-7

Author: mikolalysenko

.github/workflows/ci.yml

@@ -451,7 +451,9 @@ jobs:
         if: matrix.suite == 'e2e_gem'
         uses: ruby/setup-ruby@319994f95fa847cf3fb3cd3dbe89f6dcde9f178f # v1.295.0
         with:
-          ruby-version: '3.2.11'
+          # 3.2.11 was removed from setup-ruby's catalog; 3.2.10 is the
+          # newest 3.2.x available on the GitHub-hosted runner.
+          ruby-version: '3.2.10'
           bundler-cache: false
 
       - name: Run e2e tests