fix: check if nuget source already added

Author: meaboutsoftware

.github/workflows/chapter-4-workflow.yml

@@ -55,12 +55,15 @@ jobs:
         with:
           dotnet-version: 10.0.x
       - name: Add Evolutionary Architecture Nuget Source
-        uses: evolutionary-architecture/evolutionary-architecture-by-example/.github@main
-        with:
-          github-token: ${{ secrets.GITHUB_TOKEN }}
-          owner: ${{ github.repository_owner }}
-          path: ${{ env.CHAPTER_DIR }}
-          nuget-source-name: ${{ env.NUGET_SOURCE_NAME }}
+        run: |
+          if ! dotnet nuget list source | grep -q "${{ env.NUGET_SOURCE_NAME }}"; then
+            dotnet nuget add source \
+              https://nuget.pkg.github.com/${{ inputs.owner }}/index.json \
+              --name ${{ env.NUGET_SOURCE_NAME }} \
+              --username ${{ github.actor }} \
+              --password ${{ inputs.github-token }} \
+              --store-password-in-clear-text
+          fi
 
       - name: Restore dependencies
         run: dotnet restore