ci : re-add the .zip extension to the Windows artifacts

This will only be an "internal" name for the github build artifacts
which are uploaded from jobs. The release job will then download these
and unpack them and remove the extra .zip extension.

Author: danbev

.github/workflows/build.yml

@@ -610,7 +610,7 @@ jobs:
                 github.event.inputs.pre_release_tag != '' }}
         uses: actions/upload-artifact@v4
         with:
-          name: whisper-bin-${{ matrix.arch }}
+          name: whisper-bin-${{ matrix.arch }}.zip
           path: "build/bin*/${{ matrix.build }}"
 
   windows-blas:
@@ -693,7 +693,7 @@ jobs:
                 github.event.inputs.pre_release_tag != '' }}
         uses: actions/upload-artifact@v4
         with:
-          name: whisper-blas-bin-${{ matrix.arch }}
+          name: whisper-blas-bin-${{ matrix.arch }}.zip
           path: "build/bin*/${{ matrix.build }}"
 
   windows-cublas:
@@ -890,7 +890,7 @@ jobs:
                 github.event.inputs.pre_release_tag != '' }}
         uses: actions/upload-artifact@v4
         with:
-          name: whisper-cublas-${{ matrix.cuda-toolkit }}-bin-${{ matrix.arch }}
+          name: whisper-cublas-${{ matrix.cuda-toolkit }}-bin-${{ matrix.arch }}.zip
           path: "build/bin*/${{ matrix.build }}"
 
   emscripten: