Fix vsix name in generate script

The vsix still uses a dash.  The @ is only used within the cli itself.

Author: code-asher

fixtures/generate.bash

@@ -121,8 +121,8 @@ mock changelog
 EOF
       cp "$dir/icon.png" "$dest/extension/images/icon.png"
       pushd "$dest" >/dev/null
-      rm -f "$publisher.$name@$version.vsix"
-      zip -r "$publisher.$name@$version.vsix" * -q
+      rm -f "$publisher.$name-$version.vsix"
+      zip -r "$publisher.$name-$version.vsix" * -q
       popd >/dev/null
     done < "$dir/versions"
   done < "$dir/names"