fix: use explicit path for Git safe.directory in containers

- Changed from $GITHUB_WORKSPACE to explicit path /__w/sourcegit/sourcegit
- Fixes variable expansion issue in Ubuntu 24.04 containers
- Ensures Git operations work correctly in containerized builds

Author: biancode

.github/workflows/build.yml

@@ -42,7 +42,7 @@ jobs:
         uses: actions/checkout@v4
       - name: Configure Git safe directory
         if: startsWith(matrix.runtime, 'linux-')
-        run: git config --global --add safe.directory $GITHUB_WORKSPACE
+        run: git config --global --add safe.directory /__w/sourcegit/sourcegit
       - name: Setup .NET
         uses: actions/setup-dotnet@v4
         with: