Contains:
- performance gain
- T611: svn:external support
Plan:
- [x] Deploy package
- [x] Restart service swh-worker@loader_svn and swh-worker@loader_high_priority
- [x] Trigger scheduling of save code now on known origins with externals
- [ ] T3870: Analyze results [1]
[1] logs: http://kibana0.internal.softwareheritage.org:5601/goto/3478f6c5dd9f9662ce3eccdd6b9ac169