Use tduffield branch of github-changelog-generator

This branch fixes a number of bugs in the changelog generator, and
supports the type of behavior that we want when generating our
changelog. There is a PR open against
upstream (skywinder/github-changelog-generator#453) to merge this
upstream.

As part of this, we can now generate the changelog on every commit.

Signed-off-by: Tom Duffield <tom@chef.io>

1 files changed, 2 insertions, 1 deletions

diff --git a/Gemfile b/Gemfile
index 782a85357d..c03ce1c5d4 100644
--- a/Gemfile
+++ b/Gemfile
@@ -78,7 +78,8 @@ group(:development, :test) do
 end
 
 group(:changelog) do
-  gem "github_changelog_generator"
+  gem "github_changelog_generator", git: "https://github.com/tduffield/github-changelog-generator", branch: "adjust-tag-section-mapping"
+  gem "mixlib-install"
 end
 
 group(:travis) do