specifying and updating bundler

unfortunately, bundler fails if it finds a 2.0 lockfile.

for this and other use-cases, it would be great to

a) specify a specific bundler version
b) have a task to update it

is this a suitable place to propse this feature?

Start by locating the repository's Bundler and lockfile handling, then reproduce the failure with a 2.0 lockfile. Define how a specific Bundler version would be selected and how an update task would be invoked; the feature is done when both requested use cases are supported and covered by the project's relevant checks.

Written by the indexing model from the issue text.