NIFI-13372 Add processor DeleteSFTP

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Summary

Adds new processor DeleteSFTP to the bundle standard-processors.

See issue NIFI-13372 for the motivation behind the addition.

Tracking

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Issue Tracking

• [x] Apache NiFi Jira issue created

Pull Request Tracking

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

Pull Request Formatting

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

Verification

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Build

• [x] Build completed using mvn clean install -P contrib-check
  • [x] JDK 21

Licensing

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

Documentation

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