Fix transcription error inlining post-bugsplat-windows/action.yaml.

The copied logic replaced:
```
cd _artifacts
tar -xJf ...
```
with the one-liner:
```
tar -xJf ... -C _artifacts
```
The trouble is that `tar`'s `-C` switch is order-sensitive: it affects the
options that *follow* it on the command line.

.github/workflows/build.yaml

@@ -394,8 +394,7 @@ jobs:
       - name: Extract viewer pdb
         if: env.BUGSPLAT_USER && env.BUGSPLAT_PASS
         shell: bash
-        run: |
-          tar -xJf "${{ needs.build.outputs.viewer_channel }}.sym.tar.xz" -C _artifacts
+        run: tar -C _artifacts -xJf "${{ needs.build.outputs.viewer_channel }}.sym.tar.xz"
       - name: Post Windows symbols
         if: env.BUGSPLAT_USER && env.BUGSPLAT_PASS
         uses: secondlife-3p/symbol-upload@v10