Arvados

dotenv 3.0 was released yesterday. Because of that, with a freshly pulled bullseye-slim image:

$ ./run-build-test-packages-one-target.sh --target debian11 --arch amd64 --only-build python3-arvados-python-client --force-build --force-test
…
Install of ruby-2.7.2 - #complete 
Ruby was built without documentation, to build it run: rvm docs generate-ri
Creating alias default for ruby-2.7.2...
Successfully installed bundler-2.2.19
1 gem installed
ERROR:  Error installing fpm:
        The last version of dotenv (>= 0) to support your Ruby & RubyGems was 2.8.1. Try installing it with `gem install dotenv -v 2.8.1` and then running the current command again
        dotenv requires Ruby version >= 3.0. The current ruby version is 2.7.2.137.
Successfully installed stud-0.0.23
The command '/bin/bash -c gpg --import --no-tty /tmp/mpapis.asc &&     gpg --import --no-tty /tmp/pkuczynski.asc &&     curl -L https://get.rvm.io | bash -s stable &&     /usr/local/rvm/bin/rvm install 2.7 -j $(grep -c processor /proc/cpuinfo) --disable-binary &&     /usr/local/rvm/bin/rvm alias create default ruby-2.7 &&     echo "gem: --no-document" >> ~/.gemrc &&     /usr/local/rvm/bin/rvm-exec default gem install bundler --version 2.2.19 &&     /usr/local/rvm/bin/rvm-exec default gem install fpm --version 1.15.1' returned a non-zero code: 1

I assume this problem applies to every Docker image where we install Ruby 2.7. Note this happens before we run any Arvados code, so the fix has to go in the Dockerfile. (In other words, while this looks a lot like #21384, we can't fix it the same way.)