last_activity_at not updated when creating or deleting branch

Summary

The last_activity_at is not updated when creating or deleting branch

Steps to reproduce

Create or delete a branch, wait an hour (ie #235448), access project data with api api/v4/projects/XXX

The last last_activity_at attribute not change

What is the current bug behavior?

The last_activity_at is not updated when creating ou deleting branch

What is the expected correct behavior?

update last_activity_at when reating or deleting branch

Results of GitLab environment info

13.6.3-ee*

Results of GitLab application Check

Expand for output related to the GitLab application check

(For installations with omnibus-gitlab package run and paste the output of:
sudo gitlab-rake gitlab:check SANITIZE=true)
(For installations from source run and paste the output of:
sudo -u git -H bundle exec rake gitlab:check RAILS_ENV=production SANITIZE=true)
(we will only investigate if the tests are passing)

Possible fixes