fix: Gemfile.lock to reduce vulnerabilities (#75)
fix: Gemfile.lock to reduce vulnerabilities (#75)

The following vulnerabilities are fixed with an upgrade:
- https://snyk.io/vuln/SNYK-RUBY-HAML-20341

Latest report for apiaryio/apiblueprint.org:
https://snyk.io/test/github/apiaryio/apiblueprint.org
apiaryio/apiblueprint.org,apiaryio/apiblueprint.org,apiaryio/apiblueprint.org