Pipeline shared cache "No URL provided, cache will be not uploaded to shared cache server" on one specific project

Summary

Using a shared cache on a specific project or export of a project (forking makes the problem go away) causes the runner to be unaware of the URL for caching. The same .gitlab.ci.yml file is able to cache when inserted into another project using the same runners.

Steps to reproduce

So far this only reproducible on our project.

Example Project

Unable to reproduce in another project. Using GitLab Enterprise Edition 12.7.5-ee

What is the current bug behavior?

We create a very simple pipeline with caching as per the example here. In one project caching is successful (Uploading cache.zip to http://mini-io-ip-and-port/runner/project/project-id/static_key) in the other we get "No URL provided, cache will be not uploaded to shared cache server. Cache will be stored only locally." Both projects execute jobs on the same runner.

What is the expected correct behavior?

We expect caching to be successful in both projects.

Relevant logs and/or screenshots

Log from caching failure

Checking cache for static_key-15...
00:01
 Successfully extracted cache
 No URL provided, cache will not be downloaded from shared cache server. Instead a local version of cache will be extracted. 
$ echo "Hello"
00:01
 Hello
 $ ls -la
 total 8
 drwxrwxrwx 2 root root 4096 Feb  4 10:39 .
 drwxrwxrwx 4 root root 4096 Feb  4 10:39 ..
 $ rm -rf vendor
 $ mkdir vendor/
 $ echo "build" > vendor/hello.txt
Running after script...
00:00
 $ echo "World"
 World
Creating cache static_key-15...
00:01
 vendor/: found 2 matching files                    
 No URL provided, cache will be not uploaded to shared cache server. Cache will be stored only locally. 
 Created cache
 Job succeeded

Output of checks

This bug happens on GitLab Enterprise Edition 12.7.5-ee.