Activesupport version too low for middleman version 4.4.2

[bendangelo]

Bundler could not find compatible versions for gem "activesupport":
In snapshot (Gemfile.lock):
activesupport (>= 6.1.4.6)

In Gemfile:
middleman (~> 4.4.2) was resolved to 4.4.2, which depends on
middleman-core (= 4.4.2) was resolved to 4.4.2, which depends on
activesupport (>= 6.1, < 7.0)

middleman-google-analytics (~> 3.0) was resolved to 3.0.0, which depends on
  activesupport (>= 4.1, < 5.1)

Running bundle update will rebuild your snapshot from scratch, using only
the gems in your Gemfile, which may resolve the conflict.

Please upgrade the activesupport version.

[danielbayerlein]

@bendangelo Would you like to provide a PR? That would be great!