Undefined method 'colorize' for 'nil:NilClass' error when delivering

[sangaline]

Whenever I run git reflow deliver, I get the following error:

Here's the status of your review:
Traceback (most recent call last):
	10: from /home/sangaline/.gem/ruby/2.7.0/bin/git-reflow:23:in `<main>'
	 9: from /home/sangaline/.gem/ruby/2.7.0/bin/git-reflow:23:in `load'
	 8: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/exe/git-reflow:19:in `<top (required)>'
	 7: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/exe/git-reflow:19:in `public_send'
	 6: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow.rb:52:in `method_missing'
	 5: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/workflow.rb:184:in `block in command'
	 4: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/workflows/core.rb:301:in `block in <class:Core>'
	 3: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/workflow.rb:184:in `block in command'
	 2: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/workflows/core.rb:209:in `block in <class:Core>'
	 1: from /home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/git_server/pull_request.rb:122:in `display_pull_request_summary'
/home/sangaline/.gem/ruby/2.7.0/gems/git_reflow-0.9.4/lib/git_reflow/git_server/git_hub.rb:165:in `colorized_build_description': undefined method `colorize' for nil:NilClass (NoMethodError)

As you can see from the trace, I'm using the latest git-reflow version 0.9.4 with Ruby 2.7.