CI: Do not cancel in-progress JS artifact builds

It might be useful to have these artifacts, even for older commits. As
an added bonus, this causes the JS benchmarks to run as well giving us
more datapoints.

.github/workflows/js-artifacts.yml

@@ -27,7 +27,6 @@ jobs:
 
     concurrency:
       group: ${{ github.workflow }}-${{ matrix.os_name }}
-      cancel-in-progress: true
 
     steps:
       - name: Checkout LadybirdBrowser/ladybird