YAML.safe_load fails with Ruby 3.1

[yysaki]

Hello.

When my repository try to upgrade ruby to 3.1, I encountered ArgumentError in convergence apply .
According to ruby/psych#533, psych 4.x included a breaking change.

convergence/lib/convergence/config.rb

Line 48 in 0cfc4db

setting = YAML.safe_load(ERB.new(File.read(yaml_path)).result, [], [], true)

I think to use safe_load with newer options like aliases: true fixes this error.
But, what we need to consider is that we may need to drop support for older ruby 2.5 and below which are not support this option.
(My folked repository's test work with 2.5, but ruby doc doesn't exist this options...)

I will create PR to fix this error.

Reproduction:

% ruby -v
ruby 3.1.0p0 (2021-12-25 revision fb4df44d16) [x86_64-darwin20]
% cat database.yml
adapter: mysql
database: example_database
host: 127.0.0.1
username: root
password:
% bundle exec convergence apply schema.rb -c database.yml
Calling `DidYouMean::SPELL_CHECKERS.merge!(error_name => spell_checker)' has been deprecated. Please call `DidYouMean.correct_error(error_name, spell_checker)' instead.
Calling `DidYouMean::SPELL_CHECKERS.merge!(error_name => spell_checker)' has been deprecated. Please call `DidYouMean.correct_error(error_name, spell_checker)' instead.
bundler: failed to load command: convergence (/Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bin/convergence)
ArgumentError: wrong number of arguments (given 4, expected 1)
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/3.1.0/psych.rb:323:in `safe_load'
  /Users/yysaki/ghq/github.com/yysaki/convergence/lib/convergence/config.rb:48:in `load'
  /Users/yysaki/ghq/github.com/yysaki/convergence/lib/convergence/cli.rb:58:in `config'
  /Users/yysaki/ghq/github.com/yysaki/convergence/lib/convergence/cli.rb:29:in `apply'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.0.1/lib/thor/command.rb:27:in `run'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.0.1/lib/thor/invocation.rb:127:in `invoke_command'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.0.1/lib/thor.rb:392:in `dispatch'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/gems/thor-1.0.1/lib/thor/base.rb:485:in `start'
  /Users/yysaki/ghq/github.com/yysaki/convergence/bin/convergence:6:in `<top (required)>'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bin/convergence:25:in `load'
  /Users/yysaki/.anyenv/envs/rbenv/versions/3.1.0/lib/ruby/gems/3.1.0/bin/convergence:25:in `<top (required)>'