Bump gitlab_git to 7.1.11 to fix bug where viewing a tag on a project with submodules would return a 500 error

Closes https://github.com/gitlabhq/gitlabhq/issues/8411

CHANGELOG

@@ -1,6 +1,7 @@
 Please view this file on the master branch, on stable branches it's out of date.
 
 v 7.11.0 (unreleased)
+  - Fix broken view when using a tag to display a tree that contains git submodules (Stan Hu)
   - Make Reply-To config apply to change e-mail confirmation and other Devise notifications (Stan Hu)
   - Add application setting to restrict user signups to e-mail domains (Stan Hu)
   - Don't allow a merge request to be merged when its title starts with "WIP".

Gemfile

@@ -39,7 +39,7 @@ gem "browser"
 
 # Extracting information from a git repository
 # Provide access to Gitlab::Git library
-gem "gitlab_git", '~> 7.1.10'
+gem "gitlab_git", '~> 7.1.11'
 
 # Ruby/Rack Git Smart-HTTP Server Handler
 gem 'gitlab-grack', '~> 2.0.2', require: 'grack'

Gemfile.lock

@@ -215,7 +215,7 @@ GEM
       mime-types (~> 1.19)
     gitlab_emoji (0.1.0)
       gemojione (~> 2.0)
-    gitlab_git (7.1.10)
+    gitlab_git (7.1.11)
       activesupport (~> 4.0)
       charlock_holmes (~> 0.6)
       gitlab-linguist (~> 3.0)