error I got running instructions

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Gems updated: benchmark bigdecimal bundler cgi csv date delegate did_you_mean etc fcntl fiddle fileutils forwardable getoptlong io-console ipaddr irb reline json logger matrix mutex_m digest net-pop net-protocol net-smtp observer open3 openssl ostruct prime pstore psych racc rdoc readline readline-ext rexml rss singleton stringio strscan timeout tracer uri webrick yaml zlib
+ su lobsters -c 'gem install rake -v 13.0.1'
Successfully installed rake-13.0.1
1 gem installed
+ su lobsters -c 'bundle config set no-cach '\''true'\'''
Calling `DidYouMean::SPELL_CHECKERS.merge!(error_name => spell_checker)' has been deprecated. Please call `DidYouMean.correct_error(error_name, spell_checker)' instead.
+ su lobsters -c 'bundle install'
Calling `DidYouMean::SPELL_CHECKERS.merge!(error_name => spell_checker)' has been deprecated. Please call `DidYouMean.correct_error(error_name, spell_checker)' instead.
Fetching gem metadata from https://rubygems.org/.........
Your bundle is locked to mimemagic (0.3.5), but that version could not be found
in any of the sources listed in your Gemfile. If you haven't changed sources,
that means the author of mimemagic (0.3.5) has removed it. You'll need to update
your bundle to a version other than mimemagic (0.3.5) that hasn't been removed
in order to install.
The command '/bin/bash -c set -xe;     apk add --no-cache --virtual .build-deps         build-base         curl         gcc         git         gnupg         linux-headers         mariadb-connector-c-dev         mariadb-dev         sqlite-dev;     export PATH=/lobsters/.gem/ruby/2.7.0/bin:$PATH;     export SUPATH=$PATH;     export GEM_HOME="/lobsters/.gem";     export GEM_PATH="/lobsters/.gem";     export BUNDLE_PATH="/lobsters/.bundle";     cd /lobsters;     su lobsters -c "gem install bundler --user-install";     su lobsters -c "gem update";     su lobsters -c "gem install rake -v 13.0.1";     su lobsters -c "bundle config set no-cach 'true'";     su lobsters -c "bundle install";     if [ "${DEVELOPER_BUILD,,}" != "true" ];     then         apk del .build-deps;     fi;     mv /lobsters/Gemfile /lobsters/Gemfile.bak;     mv /lobsters/Gemfile.lock /lobsters/Gemfile.lock.bak;' returned a non-zero code: 7
make: *** [Makefile:21: build] Error 7

[rain-1]

git submodule update --remote fixed it.