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=> ERROR [stage-0 6/9] RUN useradd -G www-data,root -u $uid -d /home/$user $user                                                            0.4s
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 > [stage-0 6/9] RUN useradd -G www-data,root -u $uid -d /home/$user $user:
#11 0.400 useradd: invalid user ID '-d'
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executor failed running [/bin/sh -c useradd -G www-data,root -u $uid -d /home/$user $user]: exit code: 3
ERROR: Service 'app' failed to build : Build failed