Upgrading failing with: The "before-server" Nginx outlet is missing... discourse_docker is not compatible with the chosen Discourse version

It’s not a disk space issue:

df -h
Filesystem      Size  Used Avail Use% Mounted on
tmpfs           588M  1.1M  587M   1% /run
/dev/sda2       118G   79G   34G  71% /
tmpfs           2.9G     0  2.9G   0% /dev/shm
tmpfs           5.0M     0  5.0M   0% /run/lock
tmpfs           588M   12K  588M   1% /run/user/1001

The server doesn’t have any swap but it has 6 GB RAM:

free -h
               total        used        free      shared  buff/cache   available
Mem:           5.7Gi       793Mi       1.2Gi       1.0Mi       4.1Gi       5.0Gi
Swap:             0B          0B          0B

Do you think a swap disk is needed?

There were no other errors but I could post the whole of the ./launcher rebuild app output if you think that might help?