MinIO Upgrade to 8.6.0 causes compilation error

[manu-schaaf]

The upgrade of io.minio.minio from 8.5.6 to 8.6.0 in #137 caused an update to the okhttp dependency, breaking MinIO related code in DUUI.

[ERROR] Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.9.0:compile (default-compile) on project DockerUnifiedUIMAInterface: Compilation failure
[ERROR] <snip>/DockerUnifiedUIMAInterface/src/main/java/org/texttechnologylab/DockerUnifiedUIMAInterface/document_handler/DUUIMinioDocumentHandler.java:[26,13] cannot access okhttp3.HttpUrl
[ERROR]   class file for okhttp3.HttpUrl not found