Add bash shell to Copy Dlls step in tests workflow

Author: JunaMeinhold

.github/workflows/tests.yml

@@ -31,6 +31,7 @@ jobs:
       run: dotnet build
 
     - name: Copy Dlls
+      shell: bash
       run: |
         mkdir -p Hexa.NET.Utilities.Tests/bin/Debug/net8.0
         cp -r Hexa.NET.Utilities/runtimes Hexa.NET.Utilities.Tests/bin/Debug/net8.0/