ci: fix gh status check (#366)

As pointed in the below comment:
#362 (comment)

Author: v1v

.ci/jobs/apm-aws-lambda-smoketests-mbp.yml

@@ -14,7 +14,7 @@
         discover-pr-origin: merge-current
         discover-tags: false
         head-filter-regex: '(main|PR-.*)'
-        notification-context: 'apm-ci'
+        notification-context: 'apm-ci-smoke-test'
         repo: apm-aws-lambda
         repo-owner: elastic
         credentials-id: 2a9602aa-ab9f-4e52-baf3-b71ca88469c7-UserAndToken