Fix workflow matrix configuration

Author: ddc

.github/workflows/workflow.yml

@@ -5,20 +5,15 @@ name: CI/CD Pipeline
     branches: ["**"]
     tags: ['v*']
 
-env:
-  PYTHON_VERSIONS: '["3.12", "3.13"]'
-  OS_VERSIONS: '["ubuntu-latest", "windows-latest", "macos-latest"]'
-
-
 jobs:
   test:
     name: Test Python ${{ matrix.python-version }} on ${{ matrix.os }}
     runs-on: ${{ matrix.os }}
     strategy:
       fail-fast: false
       matrix:
-        os: ${{ fromJSON(env.OS_VERSIONS) }}
-        python-version: ${{ fromJSON(env.PYTHON_VERSIONS) }}
+        os: ["ubuntu-latest", "windows-latest", "macos-latest"]
+        python-version: ["3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4
 
@@ -53,8 +48,8 @@ jobs:
     if: startsWith(github.ref, 'refs/tags/v')
     strategy:
       matrix:
-        os: ${{ fromJSON(env.OS_VERSIONS) }}
-        python-version: ${{ fromJSON(env.PYTHON_VERSIONS) }}
+        os: ["ubuntu-latest", "windows-latest", "macos-latest"]
+        python-version: ["3.12", "3.13"]
     steps:
       - uses: actions/checkout@v4