fix: upgrade standard-version from 9.0.0 to 9.1.0 (#250)

Snyk has created this PR to upgrade standard-version from 9.0.0 to 9.1.0.

See this package in npm:
https://www.npmjs.com/package/standard-version

See this project in Snyk:
https://app.snyk.io/org/nodeshift-agg/project/994c93bd-1c82-4043-8972-3d0873d1a8ec?utm_source=github&utm_medium=upgrade-pr