fix publishing to OVSX

Author: sumneko

.github/workflows/build.yml

@@ -101,4 +101,6 @@ jobs:
 
       - name: Publish to Open VSX Registry
         if: startsWith(github.ref, 'refs/tags/')
-        run: ovsx publish -i ${{ steps.vars.outputs.PKG_NAME }} -p ${{ secrets.OVSX_TOKEN }}
+        run: |
+          npm install -g ovsx
+          ovsx publish -i ${{ steps.vars.outputs.PKG_NAME }} -p ${{ secrets.OVSX_TOKEN }}