Limit number of workers per profile

We see random timeouts and creation of ceph osd blocklist  in the e2e
runner host. Check if reducing the load by limiting the number of
workers fixes the issues.

Signed-off-by: Nir Soffer <nsoffer@redhat.com>

.github/workflows/e2e.yaml

@@ -11,6 +11,9 @@ on:  # yamllint disable-line rule:truthy
 
 env:
   NAME_PREFIX: "rdr-"
+  # Avoid random failures in overloaded runner
+  # TODO: more testing.
+  MAX_WORKERS: 1
 
 jobs:
   e2e-rdr:
@@ -41,7 +44,7 @@ jobs:
     - name: Start clusters
       working-directory: test
       run: |
-        drenv start --name-prefix ${{ env.NAME_PREFIX }} envs/regional-dr.yaml
+        drenv start --max-workers ${{ env.MAX_WORKERS }} --name-prefix ${{ env.NAME_PREFIX }} envs/regional-dr.yaml
         cp ~/.config/drenv/${{ env.NAME_PREFIX }}rdr/config.yaml ../e2e/config.yaml
 
     - name: Deploy ramen