add e2e test for issue 9923

[aalves08]

Summary

Fixes #9923

Occurred changes and/or fixed issues

• Add e2e test to prevent regression of issue Switch to Chinese. The content of the Severity drop-down box in Alerting Rules should not be translated into Chinese. #9923 where changing language to chinese should NOT affect value of severity in PrometheusRules

Technical notes summary

Areas or cases that should be tested

Areas which could experience regressions

Screenshot/Video

Checklist

• The PR is linked to an issue and the linked issue has a Milestone, or no issue is needed
• The PR has a Milestone
• The PR template has been filled out
• The PR has been self reviewed
• The PR has a reviewer assigned
• The PR has automated tests or clear instructions for manual tests and the linked issue has appropriate QA labels, or tests are not needed
• The PR has reviewed with UX and tested in light and dark mode, or there are no UX changes

[rak-phillip]

LGTM