[Stack Monitoring] fix beats pages test-subj attributes

[klacabane]

Summary

Fixes functional tests that rely on the test-subj attribute to target dom elements #114802

Testing

• set render_react_app to true
• start test server node scripts/functional_tests_server --config x-pack/test/functional/config.js
• run tests node scripts/functional_test_runner --config x-pack/test/functional/config.js --grep "Monitoring app beats"

...
...
     └-> "after all" hook for "cluster status bar shows correct information"
     └-> "after all" hook for "cluster status bar shows correct information"
   └-> "after all" hook in "Monitoring app"

5 passing (2.0m)

[elasticmachine]

Pinging @elastic/stack-monitoring (Team:Monitoring)

[elasticmachine]

Pinging @elastic/logs-metrics-ui (Team:logs-metrics-ui)

[kibanamachine]

💚 Build Succeeded

• continuous-integration/kibana-ci/pull-request
• Commit: 6381929
• Storybooks Preview

Metrics [docs]

Async chunks

Total size of all lazy-loaded chunks that will be downloaded as the user navigates the app

id	before	after	diff
monitoring	1.1MB	1.1MB	-50.0B

History

• 💔 Build #160539 failed 1c5f2b3

To update your PR or re-run it, just comment with:
@elasticmachine merge upstream