ci: include Ruby 3.4 on Windows (#4756)

**Which issue(s) this PR fixes**: 
Fixes #

**What this PR does / why we need it**: 
[RubyInstaller
3.4.1](https://github.com/oneclick/rubyinstaller2/releases/tag/RubyInstaller-3.4.1-1)
was released.
So we can use Ruby 3.4 on Windows in CI.

**Docs Changes**:

**Release Note**:

Signed-off-by: Shizuo Fujita <fujita@clear-code.com>

Author: Watson1978

.github/workflows/test.yml

@@ -27,9 +27,6 @@ jobs:
       matrix:
         os: ['ubuntu-latest', 'macos-latest', 'windows-latest']
         ruby-version: ['3.4', '3.3', '3.2', '3.1']
-        exclude:
-          - os: 'windows-latest'
-            ruby-version: '3.4'
 
     name: Ruby ${{ matrix.ruby-version }} on ${{ matrix.os }}
     steps: