github/workflows: skip robustness tests in forks

Robustness tests require a larger instance size, which user forks cannot
access. It also tries to trigger an ARM64 build that runs on actuated
infrastructure. By not running them on user forks, contributors won't be
notified that their builds are failing due to timeouts trying to run the
job, while the tests will still run on etcd-io/bbolt pull requests and
commits.

Signed-off-by: Ivan Valdes <ivan@vald.es>

.github/workflows/robustness_template.yaml

@@ -18,6 +18,8 @@ permissions: read-all
 
 jobs:
   test:
+    # this is to prevent the job to run at forked projects
+    if: github.repository == 'etcd-io/bbolt'
     timeout-minutes: 210
     runs-on: ${{ fromJson(inputs.runs-on) }}
     steps: