LiquibaseEndpoint always uses defaultSchema instead of liquibaseSchema

[xyraclius]

🚀 Overview

This PR fixes the /actuator/liquibase endpoint to respect the spring.liquibase.liquibase-schema property. Previously, the endpoint always used default-schema, even when liquibase-schema was configured.

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🔥 Motivation

When application tables and Liquibase’s internal tables use separate schemas, the /actuator/liquibase endpoint ignores liquibase-schema and only reports changes from default-schema. This results in misleading output and prevents accurate monitoring of Liquibase change sets.

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🔧 Changes

• Updated LiquibaseEndpoint.createReport to:
  • Use liquibase.getLiquibaseSchema() when configured.
  • Fall back to liquibase.getDefaultSchema() otherwise.
• Applied database.setDefaultSchemaName(schemaToUse) only when a schema is present.
• Added unit test invokeWithLiquibaseSchema() to verify correct behavior.

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✅ Benefits

• /actuator/liquibase now produces accurate reports when spring.liquibase.liquibase-schema is configured.
• Supports schema separation between Liquibase internal tables and application domain tables.
• Backward compatible — existing setups that rely on default-schema remain unaffected.

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🔖 Related Issue

Closes #47290

[snicoll]

Thanks @xyraclius!