Switch from Docker image settings to WorkerVersion.feature

https://redmine.teklia.com/issues/8011

docker.ingest_image and docker.init_elements_image are removed and replaced by WorkerVersion.feature. This field is not set automatically by anything, but the system checks already mention the arkindex update_system_workers since it will be implemented later.

changed milestone to %Arkindex 1.6.3

requested review from @babadie

assigned to @erouchet

Please rebase

added 4 commits

• 707dc60c...66908a24 - 3 commits from branch master
• a775631f - Switch from Docker image settings to WorkerVersion.feature

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added 2 commits

• bb7b53e1 - 1 commit from branch master
• f0883774 - Switch from Docker image settings to WorkerVersion.feature

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added 2 commits

• d8466ac0 - Custom exception message
• dc13e721 - Nuke tasks setting

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added 1 commit

• ab7ae69f - Add comment for cache_clear

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resolved all threads

added 5 commits

• 8f709a1d - 1 commit from branch master
• 156027aa - Switch from Docker image settings to WorkerVersion.feature
• c5a83699 - Custom exception message
• 6fdc0b21 - Nuke tasks setting
• 428adde8 - Add comment for cache_clear

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When setting a featuer from the admin, I get an exception

added 2 commits

• b136949d - Mixup with secret Django methods
• fc1d73a0 - Prevent HTTP 500 errors when a check constraint fails

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mentioned in issue #1832 (closed)

added 8 commits

• fc1d73a0...2444f59c - 2 commits from branch master
• 407beff5 - Switch from Docker image settings to WorkerVersion.feature
• 37a0a15a - Custom exception message
• 33145a01 - Nuke tasks setting
• 4c7fd12b - Add comment for cache_clear
• e630561e - Mixup with secret Django methods
• e6e25777 - Prevent HTTP 500 errors when a check constraint fails

Compare with previous version

enabled an automatic merge when the pipeline for e6e25777 succeeds

merged