When parentheses are included in the issue template, the template cannot be rendered

Summary

In the project, there is an issue template named: image

Then when the template with this name is selected, the template cannot be rendered, and the loading icon in the drop-down box keeps rotating. At first, I thought that there was illegal content in the md, but after all the content was deleted, the problem remained. image

Until another template with the same content is created, and the parentheses are removed from the template file name, everything returns to normal. image

Steps to reproduce

As shown in the problem description, if the file name of the issue template contains parentheses, the problem can be reproduced.

Example Project

https://gitlab.com/nicelife8407/test-template/-/issues/new

What is the current bug behavior?

The issue template cannot be loaded normally when creating an Issue.

What is the expected correct behavior?

Able to load the issue template normally.

Relevant logs and/or screenshots

Output of checks

This bug happens on GitLab.com

Results of GitLab environment info

Expand for output related to GitLab environment info 

(For installations with omnibus-gitlab package run and paste the output of:
`sudo gitlab-rake gitlab:env:info`)

(For installations from source run and paste the output of:
`sudo -u git -H bundle exec rake gitlab:env:info RAILS_ENV=production`)

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