Standardized use of LocalCluster in API integration tests

[nibix]

Description

This changes the implementation of the integration extending AbstractApiIntegrationTest in a way that they use the LocalCluster test infrastructure in way that aligns more its common use. This got necessary because I need to do some test framework extensions for #5399 ; however, the present implementation creates some impediments for these extensions.

• Category: Test maintenance
• Why these changes are required? Standardized use of test framework
• What is the old behavior before changes and new behavior after changes? No changes.

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Check List

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