The version update has been cherrypicked from master where bundle has
been updated to 2.2.20. It was then failing to run with:
./result/bin/foreman
Warning: the running version of Bundler (2.1.4) is older than the version that created the lockfile (2.2.20). We suggest you to upgrade to the version that created the lockfile by running `gem install bundler:2.2.20`.
Traceback (most recent call last):
2: from ./result/bin/foreman:20:in `<main>'
1: from /nix/store/ggqacj06n6qfm1iww0bih9ph0j89wcna-bundler-2.1.4/lib/ruby/gems/2.7.0/gems/bundler-2.1.4/lib/bundler/rubygems_integration.rb:413:in `block in replace_bin_path'
/nix/store/ggqacj06n6qfm1iww0bih9ph0j89wcna-bundler-2.1.4/lib/ruby/gems/2.7.0/gems/bundler-2.1.4/lib/bundler/rubygems_integration.rb:374:in `block in replace_bin_path': can't find executable foreman for gem foreman. foreman is not currently included in the bundle, perhaps you meant to add it to your Gemfile? (Gem::Exception)