ci(release): use softprops/action-gh-release for server asset upload

Switches the build-server upload steps from the deprecated
actions/upload-release-asset@v1 to softprops/action-gh-release@v2,
which resolves intermittent socket hang up failures when attaching
release assets. Drops the now-unused upload_url output from the
create-draft-release job.

.github/workflows/release.yml

@@ -21,7 +21,6 @@ jobs:
     outputs:
       release_id: ${{ steps.release.outputs.release_id }}
       release_url: ${{ steps.release.outputs.release_url }}
-      upload_url: ${{ steps.release.outputs.upload_url }}
       prerelease: ${{ steps.meta.outputs.prerelease }}
       release_body: ${{ steps.release.outputs.release_body }}
     steps:
@@ -162,7 +161,6 @@ jobs:
 
             core.setOutput("release_id", String(release.id));
             core.setOutput("release_url", release.html_url);
-            core.setOutput("upload_url", release.upload_url);
             core.setOutput("release_body", releaseBody);
 
   build-tauri:
@@ -458,25 +456,21 @@ jobs:
 
       - name: Upload to release (Unix)
         if: runner.os != 'Windows'
-        uses: actions/upload-release-asset@v1
+        uses: softprops/action-gh-release@v2
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
-          upload_url: ${{ needs.create-draft-release.outputs.upload_url }}
-          asset_path: dist/${{ matrix.artifact }}.tar.gz
-          asset_name: ${{ matrix.artifact }}.tar.gz
-          asset_content_type: application/gzip
+          tag_name: ${{ github.ref_name }}
+          files: dist/${{ matrix.artifact }}.tar.gz
 
       - name: Upload to release (Windows)
         if: runner.os == 'Windows'
-        uses: actions/upload-release-asset@v1
+        uses: softprops/action-gh-release@v2
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
-          upload_url: ${{ needs.create-draft-release.outputs.upload_url }}
-          asset_path: dist/${{ matrix.artifact }}.zip
-          asset_name: ${{ matrix.artifact }}.zip
-          asset_content_type: application/zip
+          tag_name: ${{ github.ref_name }}
+          files: dist/${{ matrix.artifact }}.zip
 
   build-docker:
     needs: