Dependabot can't resolve your Ruby dependency files

[dependabot-preview]

Dependabot can't resolve your Ruby dependency files.

As a result, Dependabot couldn't update your dependencies.

The error Dependabot encountered was:

Bundler::VersionConflict with message: Bundler could not find compatible versions for gem "bundler":
  In Gemfile:
    appraisal (~> 2.0) was resolved to 2.4.1, which depends on
      bundler

    rails (= 4.2.11.1) was resolved to 4.2.11.1, which depends on
      bundler (>= 1.3.0, < 2.0)

  Current Bundler version:
    bundler (2.2.15)

Your bundle requires a different version of Bundler than the one you're running.
Install the necessary version with `gem install bundler:2.0.0.pre.3` and rerun bundler using `run.rb _2.0.0.pre.3_`

If you think the above is an error on Dependabot's side please don't hesitate to get in touch - we'll do whatever we can to fix it.

View the update logs.