Fix duplicated branch creation/deletion events when using Web UI

When deleting a branch, this is what was happening:

1. DeleteBranchService calls EventCreateService and creates an event.
2. The call to repository.rm_branch triggers the GitHooksService.
3. This, in turn, calls GitPushService and then calls EventCreateService again.

5145706c now makes it no longer necessary for DeleteBranchService and CreateBranchService to create an event.

Closes #4304

CHANGELOG

@@ -28,6 +28,7 @@ v 8.4.0 (unreleased)
   - Ajax filter by message for commits page
 v 8.3.3 (unreleased)
+  - Fix duplicated branch creation/deletion events when using Web UI (Stan Hu)
   - Get "Merge when build succeeds" to work when commits were pushed to MR target branch while builds were running
   - Fix project transfer e-mail sending incorrect paths in e-mail notification (Stan Hu)
   - Enable "Add key" button when user fills in a proper key (Stan Hu)

app/services/create_branch_service.rb

@@ -31,7 +31,6 @@ class CreateBranchService < BaseService
     if new_branch
       push_data = build_push_data(project, current_user, new_branch)
-      EventCreateService.new.push(project, current_user, push_data)
       project.execute_hooks(push_data.dup, :push_hooks)
       project.execute_services(push_data.dup, :push_hooks)

app/services/delete_branch_service.rb

@@ -27,7 +27,6 @@ class DeleteBranchService < BaseService
     if repository.rm_branch(current_user, branch_name)
       push_data = build_push_data(branch)
-      EventCreateService.new.push(project, current_user, push_data)
       project.execute_hooks(push_data.dup, :push_hooks)
       project.execute_services(push_data.dup, :push_hooks)