The bundle currently has mimemagic locked at 0.3.5.

[x1wins]

The bundle currently has mimemagic locked at 0.3.5.

[x1wins]

rails/rails#41750
https://stackoverflow.com/q/66919504/1399891

Trouble
rails/rails#41750 (comment)
mimemagic gem got licence problem. they did lock 0.3.x version.

Solve
i have to update Gemfile, Gemfile.lock and then push to git remote origin.
if there not updated Gemfile.lock, travis ci will make build error.

if you use docker-compose
docker-compose run --no-deps web bundle update mimemagic
if you not use docker-compose
bundle update mimemagic

[x1wins]

if not working with docker-compose run --no-deps web bundle update mimemagic
Try get below listed command

1. Change RUN bundle install to RUN bundle update in Dockerfile
2. % docker-compose -f docker-compose-dev.yml run web bundle update
3. Recover RUN bundle update to RUN bundle install in Dockerfile
4. % docker-compose -f docker-compose-dev.yml up --build