NIFI-15221 - Major upgrade to Spring 7

[pvillard31]

Summary

NIFI-15221 - Major upgrade to Spring 7

Tracking

Please complete the following tracking steps prior to pull request creation.

Issue Tracking

• [ ] Apache NiFi Jira issue created

Pull Request Tracking

• [ ] Pull Request title starts with Apache NiFi Jira issue number, such as NIFI-00000
• [ ] Pull Request commit message starts with Apache NiFi Jira issue number, as such NIFI-00000

Pull Request Formatting

• [ ] Pull Request based on current revision of the main branch
• [ ] Pull Request refers to a feature branch with one commit containing changes

Verification

Please indicate the verification steps performed prior to pull request creation.

Build

• [ ] Build completed using ./mvnw clean install -P contrib-check
  • [ ] JDK 21
  • [ ] JDK 25

Licensing

• [ ] New dependencies are compatible with the Apache License 2.0 according to the License Policy
• [ ] New dependencies are documented in applicable LICENSE and NOTICE files

Documentation

• [ ] Documentation formatting appears as expected in rendered files