(gha) Do not fail fast when running the nested vms tests

...so that we get a better sense of all the vm state rather than just
the first to fail.

Author: jpartlow

.github/workflows/pr_testing_with_nested_vms.yml

@@ -12,6 +12,7 @@ on:
 jobs:
   test-install-task:
     strategy:
+      fail-fast: false
       matrix:
         os:
           - [almalinux, '8']