Fix duplicate repositories in GitHub import page

By default, all the current user's repositories are accessible via the
/users endpoint. There's no need to traverse all the organization
repositories as well.

See:

* http://www.rubydoc.info/github/pengwynn/octokit/Octokit/Client/Repositories#repositories-instance_method
* https://developer.github.com/v3/repos/#list-your-repositories

Closes #2523

CHANGELOG

 Please view this file on the master branch, on stable branches it's out of date.
 v 8.2.0 (unreleased)
+  - Fix duplicate repositories in GitHub import page (Stan Hu)
   - Show last project commit to default branch on project home page
   - Highlight comment based on anchor in URL
   - Adds ability to remove the forked relationship from project settings screen. (Han Loong Liauw)

app/controllers/import/github_controller.rb

@@ -11,10 +11,6 @@ class Import::GithubController < Import::BaseController
   def status
     @repos = client.repos
-    client.orgs.each do |org|
-      @repos += client.org_repos(org.login)
-    end
-
     @already_added_projects = current_user.created_projects.where(import_type: "github")
     already_added_projects_names = @already_added_projects.pluck(:import_source)

spec/controllers/import/github_controller_spec.rb

@@ -41,7 +41,7 @@ describe Import::GithubController do
     it "assigns variables" do
       @project = create(:project, import_type: 'github', creator_id: user.id)
-      stub_client(repos: [@repo], orgs: [@org], org_repos: [@org_repo])
+      stub_client(repos: [@repo, @org_repo], orgs: [@org], org_repos: [@org_repo])
       get :status