`bundle_command` changes surprisingly when using a different Gemfile location

[makmic]

Hi 👋

I had some fun yesterday debugging why my rake commands in the schedule.rb somehow yielded different results than before without having changed anything to whenever.

It turns out, the bundle_command default is determined like so:

whenever/lib/whenever/setup.rb

Line 26 in 0687268

set :bundle_command, Whenever.bundler? ? "bundle exec" : ""

..which is tied to:

whenever/lib/whenever.rb

Lines 31 to 33 in 0687268

	def self.bundler?
	File.exist?(File.join(path, 'Gemfile'))
	end

Well. My seemingly unrelated change of the day was to move the Gemfile into a different location (say something like Gemfile-ruby33) and point the BUNDLE_GEMFILE env variable to that location. That's not too common, but the standard way to do so (see https://bundler.io/v2.5/man/bundle-config.1.html#LIST-OF-AVAILABLE-KEYS and bundle config gemfile)

I suggest to adjust Whenever#bundler? in a way that works in that scenario as well.

Thanks!