seml hold & duplicates

[yascho]

Hi real quick,

seml hold

• seml hold is executed correctly but ends in an error message

seml exp hold
-> CalledProcessError: Command 'scontrol hold '590528 590526 590527'' returned non-zero exit status 1.

Duplicates in database after breaking changes update

Reproduce "adding of duplicates" issue:

• add and execute e.g. grid-search experiments normally with the old version
• install new version, which updates database (with one-time warning for the conversion)
• extend grid search, duplicates are not recognized (possibly since db_collection is considered during duplicate detection)
• entire grid search is added again (not just the additional experiments)