per maven repository.
For each maven repository configured in the configuration key
maven_index_exporter::repositories, this installs:
- one timer maven_index_exporter@.timer and its associated service maven_index_exporter@.service
- one run_maven_index_exporter.sh script to compute export.fld (the script is triggered by the service)
For now, this also installs 2 maven repositories to crawl:
Related to T3746