Revert "Fix unique constraint error on 'channels_name_key' while executing metaconfig step for multi-plate experiments"
Revert "Fix unique constraint error on 'channels_name_key' while executing metaconfig step for multi-plate experiments"

This reverts commit 17880a332d9e56d316280024810dc82758a019ea.

This commit, together with right channels, leaves in the database (experiment_x.channel) non up to date channel entries that should not be there.
This produces an error in the frontend that goes away when does entries are deleted.

TissueMAPS/TmLibrary,TissueMAPS/TmLibrary,TissueMAPS/TmLibrary,TissueMAPS/TmLibrary,TissueMAPS/TmLibrary