Use graph data generation for anomaly chart tests

What does this MR do?

Part of #223780. Currently our charts specs are limited by the kinds of seed data for charts tests. In order to be able to load more shapes of data, we should make generating this data easier.

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Does this MR meet the acceptance criteria?

Conformity

• [-] Changelog entry
• [-] Documentation (if required)
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• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers
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