Do not pass secrets to environment variables

Why was it done in the first place? Today GitHub Actions is skipping Codacy and Stryker steps. I'm sure it used to work. Let's try to test if the secrets exist directly on secrets.* instead of env.*

Author: 0xced

.github/workflows/continuous-integration.yml

@@ -26,9 +26,6 @@ jobs:
       version: ${{ steps.dotnet-pack.outputs.version }}
       nupkg-filename: ${{ steps.dotnet-pack.outputs.nupkg-filename }}
       release-body: ${{ steps.tag-message.outputs.release-notes }}
-    env:
-      CODACY_PROJECT_TOKEN: ${{ secrets.CODACY_PROJECT_TOKEN }}
-      STRYKER_DASHBOARD_API_KEY: ${{ secrets.STRYKER_DASHBOARD_API_KEY }}
     steps:
       - name: Checkout git repository
         uses: actions/checkout@v3
@@ -75,7 +72,7 @@ jobs:
         with:
           files: ${{ steps.dotnet-test.outputs.coverage-reports }}
       - name: Upload coverage report to Codacy
-        if: matrix.os == 'ubuntu-latest' && env.CODACY_PROJECT_TOKEN != ''
+        if: matrix.os == 'ubuntu-latest' && secrets.CODACY_PROJECT_TOKEN != ''
         uses: codacy/codacy-coverage-reporter-action@v1
         with:
           project-token: ${{ secrets.CODACY_PROJECT_TOKEN }}
@@ -90,7 +87,7 @@ jobs:
           name: ${{ steps.dotnet-pack.outputs.nupkg-filename }}
           path: ${{ steps.dotnet-pack.outputs.nupkg-filename }}
       - name: Run mutation tests and upload report to Stryker dashboard
-        if: matrix.os == 'ubuntu-latest' && env.STRYKER_DASHBOARD_API_KEY != ''
+        if: matrix.os == 'ubuntu-latest' && secrets.STRYKER_DASHBOARD_API_KEY != ''
         run: |
           dotnet tool restore
           dotnet tool run dotnet-stryker --reporter dashboard --version ${GITHUB_REF_NAME} --dashboard-api-key ${{ secrets.STRYKER_DASHBOARD_API_KEY }}