Update all modules to Spring Boot 4.0.0 and corresponding Spring Framework versions

[coderabbitai]

Description

This issue tracks the migration of all project modules to Spring Boot 4.0.0 and the corresponding Spring Framework versions.

Context

Related to PR #127: #127

Modules to Update

The following modules need to be updated:

• spring-batch-db-examples
• spring-batch-file-examples
• spring-jasper-example
• spring-kafka-example
• spring-keycloak-example
• spring-multimodule-example (including sub-modules)
• spring-mysql-example
• spring-oracle-example
• spring-postgres-example
• spring-prometheus-grafana-example

Tasks

1. Update Spring Boot dependencies to 4.0.0
2. Update corresponding Spring Framework versions
3. Test each module after migration
4. Address any breaking changes or deprecations

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Requested by: @igorcampos-dev