Not helpful error message when using invalid bump value

[MatthewFlamm]

I'm getting error this error, when specifying an invalid bump value. It took me awhile to figure out what was wrong. A more informative error message could be supplied.

Run zwaldowski/semver-release-action@v2
  with:
    dry_run: true
    bump: patchpatch
    github_token: ***
    per_branch: false
Getting list of tags from repository
Using latest tag "0.1.0" with identifier ""
Error: Cannot read property 'toString' of null